diff --git a/config/xml/Bitrix24.Lib.ApplicationInstallations.Entity.ApplicationInstallation.dcm.xml b/config/xml/Bitrix24.Lib.ApplicationInstallations.Entity.ApplicationInstallation.dcm.xml
new file mode 100644
index 0000000..9e8c92c
--- /dev/null
+++ b/config/xml/Bitrix24.Lib.ApplicationInstallations.Entity.ApplicationInstallation.dcm.xml
@@ -0,0 +1,38 @@
+<doctrine-mapping xmlns="http://doctrine-project.org/schemas/orm/doctrine-mapping"
+                  xmlns:xs="https://www.w3.org/2001/XMLSchema"
+                  xmlns:orm="https://www.doctrine-project.org/schemas/orm/doctrine-mapping.xsd">
+    <entity name="Bitrix24\Lib\ApplicationInstallations\Entity\ApplicationInstallation"
+            table="application_installation">
+        <id name="id" type="uuid" column="id">
+
+        </id>
+
+        <field name="status" enum-type="string" column="status" nullable="false"/>
+
+        <field name="createdAt" type="carbon_immutable" column="created_at_utc" precision="3" nullable="false"/>
+
+        <field name="updatedAt" type="carbon_immutable" column="update_at_utc" precision="3" nullable="false"/>
+
+        <field name="bitrix24AccountId" type="uuid" column="bitrix_24_account_id" nullable="false" unique="true"/>
+
+        <field name="contactPersonId" type="uuid" column="contact_person_id" nullable="true"/>
+
+        <field name="bitrix24PartnerContactPersonId" type="uuid" column="bitrix_24_partner_contact_person_id"
+               nullable="true"/>
+
+        <field name="bitrix24PartnerId" type="uuid" column="bitrix_24_partner_id" nullable="true"/>
+
+        <field name="externalId" type="string" column="external_id" nullable="true"/>
+
+        <field name="portalLicenseFamily" enum-type="string" column="portal_license_family" nullable="false"/>
+
+        <field name="portalUsersCount" type="integer" column="portal_users_count" nullable="true"/>
+
+        <field name="applicationToken" type="string" column="application_token" nullable="true"/>
+
+        <field name="comment" type="text" column="comment" nullable="true"/>
+
+
+        <embedded name="applicationStatus" class="Bitrix24\SDK\Application\ApplicationStatus"/>
+    </entity>
+</doctrine-mapping>
\ No newline at end of file
diff --git a/config/xml/Bitrix24.Lib.Bitrix24Accounts.Entity.Bitrix24Account.dcm.xml b/config/xml/Bitrix24.Lib.Bitrix24Accounts.Entity.Bitrix24Account.dcm.xml
index c2e57d9..d4baa42 100644
--- a/config/xml/Bitrix24.Lib.Bitrix24Accounts.Entity.Bitrix24Account.dcm.xml
+++ b/config/xml/Bitrix24.Lib.Bitrix24Accounts.Entity.Bitrix24Account.dcm.xml
@@ -12,6 +12,8 @@
 
         <field name="memberId" type="string" column="member_id" nullable="false"/>
 
+        <field name="isMasterAccount" type="boolean" column="is_master_account" nullable="true"/>
+
         <field name="domainUrl" type="string" column="domain_url" nullable="false"/>
 
         <field name="status" enum-type="string" column="status" nullable="false"/>
@@ -24,6 +26,8 @@
 
         <field name="applicationVersion" type="integer" column="application_version" nullable="false"/>
 
+        <field name="comment" type="text" column="comment" nullable="true"/>
+
         <embedded name="authToken" class="Bitrix24\SDK\Core\Credentials\AuthToken"/>
 
         <embedded name="applicationScope" class="Bitrix24\SDK\Core\Credentials\Scope"/>
diff --git a/config/xml/Bitrix24.SDK.Application.ApplicationStatus.dcm.xml b/config/xml/Bitrix24.SDK.Application.ApplicationStatus.dcm.xml
new file mode 100644
index 0000000..2a89139
--- /dev/null
+++ b/config/xml/Bitrix24.SDK.Application.ApplicationStatus.dcm.xml
@@ -0,0 +1,7 @@
+<doctrine-mapping xmlns="http://doctrine-project.org/schemas/orm/doctrine-mapping"
+                  xmlns:xs="https://www.w3.org/2001/XMLSchema"
+                  xmlns:orm="https://www.doctrine-project.org/schemas/orm/doctrine-mapping.xsd">
+    <embeddable name="Bitrix24\SDK\Application\ApplicationStatus">
+        <field name="statusCode" type="json" nullable="true" column="status_code"/>
+    </embeddable>
+</doctrine-mapping>
\ No newline at end of file
diff --git a/src/ApplicationInstallations/Entity/ApplicationInstallation.php b/src/ApplicationInstallations/Entity/ApplicationInstallation.php
new file mode 100644
index 0000000..3aba323
--- /dev/null
+++ b/src/ApplicationInstallations/Entity/ApplicationInstallation.php
@@ -0,0 +1,447 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Bitrix24\Lib\ApplicationInstallations\Entity;
+
+use Bitrix24\Lib\AggregateRoot;
+use Bitrix24\SDK\Application\ApplicationStatus;
+use Bitrix24\SDK\Application\Contracts\ApplicationInstallations\Entity\ApplicationInstallationInterface;
+use Bitrix24\SDK\Application\Contracts\ApplicationInstallations\Entity\ApplicationInstallationStatus;
+use Bitrix24\SDK\Application\Contracts\ApplicationInstallations\Events;
+use Bitrix24\SDK\Application\Contracts\ApplicationInstallations\Events\ApplicationInstallationBlockedEvent;
+use Bitrix24\SDK\Application\Contracts\ApplicationInstallations\Events\ApplicationInstallationContactPersonLinkedEvent;
+use Bitrix24\SDK\Application\Contracts\ApplicationInstallations\Events\ApplicationInstallationCreatedEvent;
+use Bitrix24\SDK\Application\Contracts\ApplicationInstallations\Events\ApplicationInstallationFinishedEvent;
+use Bitrix24\SDK\Application\Contracts\ApplicationInstallations\Events\ApplicationInstallationUnblockedEvent;
+use Bitrix24\SDK\Application\Contracts\ApplicationInstallations\Events\ApplicationInstallationUninstalledEvent;
+use Bitrix24\SDK\Application\PortalLicenseFamily;
+use Bitrix24\SDK\Core\Exceptions\InvalidArgumentException;
+use Bitrix24\SDK\Core\Exceptions\LogicException;
+use Carbon\CarbonImmutable;
+use Symfony\Component\Uid\Uuid;
+
+/**
+ * Установка может происходить по 2 сценриям.
+ * 1) UI - Пользователь запускает установку через интерфейс.
+ * Bitrix24 отправляет первичный запрос на /install.php с параметрами:
+ * AUTH_ID, REFRESH_ID, member_id в теле запроса. Без application_token
+ * Система создаёт Bitrix24Account в статусе new.
+ * Bitrix24 отправляет событие ONAPPINSTALL на /event-handler.php и передает application_token
+ * Вызывается applicationInstalled($applicationToken) с полученным токеном.
+ * 2) Без UI - Установка инициируется прямым POST-запросом с полным набором credentials.
+ * Сразу создается Bitrix24Account. У установщика и у аккаунта вызывается метод с переданыым токеном:
+ * $bitrix24Account->applicationInstalled($applicationToken);
+ * $applicationInstallation->applicationInstalled($applicationToken);.
+ */
+class ApplicationInstallation extends AggregateRoot implements ApplicationInstallationInterface
+{
+    private ?string $applicationToken = null;
+
+    private readonly CarbonImmutable $createdAt;
+
+    private CarbonImmutable $updatedAt;
+
+    private ApplicationInstallationStatus $status = ApplicationInstallationStatus::new;
+
+    public function __construct(
+        private readonly Uuid $id,
+        private readonly Uuid $bitrix24AccountId,
+        private ApplicationStatus $applicationStatus,
+        private PortalLicenseFamily $portalLicenseFamily,
+        private ?int $portalUsersCount,
+        private ?Uuid $contactPersonId,
+        private ?Uuid $bitrix24PartnerContactPersonId,
+        private ?Uuid $bitrix24PartnerId,
+        private ?string $externalId,
+        private ?string $comment = null,
+        private $isEmitApplicationInstallationCreatedEvent = false
+    ) {
+        $this->createdAt = new CarbonImmutable();
+        $this->updatedAt = new CarbonImmutable();
+        $this->addApplicationCreatedEventIfNeeded($this->isEmitApplicationInstallationCreatedEvent);
+    }
+
+    #[\Override]
+    public function getId(): Uuid
+    {
+        return $this->id;
+    }
+
+    #[\Override]
+    public function getCreatedAt(): CarbonImmutable
+    {
+        return $this->createdAt;
+    }
+
+    #[\Override]
+    public function getUpdatedAt(): CarbonImmutable
+    {
+        return $this->updatedAt;
+    }
+
+    #[\Override]
+    public function getBitrix24AccountId(): Uuid
+    {
+        return $this->bitrix24AccountId;
+    }
+
+    #[\Override]
+    public function getContactPersonId(): ?Uuid
+    {
+        return $this->contactPersonId;
+    }
+
+    #[\Override]
+    public function getBitrix24PartnerContactPersonId(): ?Uuid
+    {
+        return $this->bitrix24PartnerContactPersonId;
+    }
+
+    #[\Override]
+    public function getBitrix24PartnerId(): ?Uuid
+    {
+        return $this->bitrix24PartnerId;
+    }
+
+    #[\Override]
+    public function getExternalId(): ?string
+    {
+        return $this->externalId;
+    }
+
+    #[\Override]
+    public function setExternalId(?string $externalId): void
+    {
+        if ('' === $externalId) {
+            throw new InvalidArgumentException('ExternalId cannot be empty string');
+        }
+
+        $this->externalId = $externalId;
+    }
+
+    #[\Override]
+    public function getStatus(): ApplicationInstallationStatus
+    {
+        return $this->status;
+    }
+
+    #[\Override]
+    public function applicationInstalled(?string $applicationToken = null): void
+    {
+        if (
+            ApplicationInstallationStatus::new !== $this->status
+            && ApplicationInstallationStatus::blocked !== $this->status
+        ) {
+            throw new LogicException(
+                sprintf(
+                    'installation was interrupted because status must be in new or blocked,but your status is %s',
+                    $this->status->value
+                )
+            );
+        }
+
+        if (null !== $applicationToken) {
+            $this->guardEmptyToken($applicationToken);
+            $this->applicationToken = $applicationToken;
+        }
+
+        $this->status = ApplicationInstallationStatus::active;
+        $this->updatedAt = new CarbonImmutable();
+
+        $this->events[] = new ApplicationInstallationFinishedEvent(
+            $this->id,
+            $this->updatedAt,
+            $this->bitrix24AccountId,
+            $this->portalLicenseFamily,
+            $this->contactPersonId,
+            $this->bitrix24PartnerContactPersonId,
+            $this->bitrix24PartnerId
+        );
+    }
+
+    #[\Override]
+    public function applicationUninstalled(?string $applicationToken = null): void
+    {
+        if (
+            ApplicationInstallationStatus::active !== $this->status
+            && ApplicationInstallationStatus::blocked !== $this->status
+        ) {
+            throw new LogicException(
+                sprintf(
+                    'installation was interrupted because status must be in active or blocked, but your status is %s',
+                    $this->status->value
+                )
+            );
+        }
+
+        if (null !== $applicationToken) {
+            $this->guardEmptyToken($applicationToken);
+            $this->guardTokenMismatch($applicationToken);
+        }
+
+        $this->status = ApplicationInstallationStatus::deleted;
+        $this->updatedAt = new CarbonImmutable();
+
+        $this->events[] = new ApplicationInstallationUninstalledEvent(
+            $this->id,
+            $this->updatedAt,
+            $this->bitrix24AccountId,
+            $this->contactPersonId,
+            $this->bitrix24PartnerId,
+            $this->bitrix24PartnerId,
+            $this->externalId
+        );
+    }
+
+    #[\Override]
+    public function markAsActive(?string $comment): void
+    {
+        if (ApplicationInstallationStatus::blocked !== $this->status) {
+            throw new LogicException(
+                sprintf(
+                    'you must be in status blocked to complete the installation, now status is «%s»',
+                    $this->status->value
+                )
+            );
+        }
+
+        $this->status = ApplicationInstallationStatus::active;
+        $this->comment = $comment;
+        $this->updatedAt = new CarbonImmutable();
+
+        $this->events[] = new ApplicationInstallationUnblockedEvent(
+            $this->id,
+            $this->updatedAt,
+            $this->comment
+        );
+    }
+
+    #[\Override]
+    public function markAsBlocked(?string $comment): void
+    {
+        if (
+            ApplicationInstallationStatus::new !== $this->status
+            && ApplicationInstallationStatus::active !== $this->status
+        ) {
+            throw new LogicException(sprintf(
+                'You can block application installation only in status new or active,but your status is «%s»',
+                $this->status->value
+            ));
+        }
+
+        $this->status = ApplicationInstallationStatus::blocked;
+        $this->comment = $comment;
+        $this->updatedAt = new CarbonImmutable();
+
+        $this->events[] = new ApplicationInstallationBlockedEvent(
+            $this->id,
+            new CarbonImmutable(),
+            $this->comment
+        );
+    }
+
+    #[\Override]
+    public function getApplicationStatus(): ApplicationStatus
+    {
+        return $this->applicationStatus;
+    }
+
+    #[\Override]
+    public function changeApplicationStatus(ApplicationStatus $applicationStatus): void
+    {
+        if ($this->applicationStatus !== $applicationStatus) {
+            $this->applicationStatus = $applicationStatus;
+            $this->updatedAt = new CarbonImmutable();
+
+            $this->events[] = new Events\ApplicationInstallationApplicationStatusChangedEvent(
+                $this->id,
+                $this->updatedAt,
+                $applicationStatus
+            );
+        }
+    }
+
+    #[\Override]
+    public function getPortalLicenseFamily(): PortalLicenseFamily
+    {
+        return $this->portalLicenseFamily;
+    }
+
+    #[\Override]
+    public function changePortalLicenseFamily(PortalLicenseFamily $portalLicenseFamily): void
+    {
+        if ($this->portalLicenseFamily !== $portalLicenseFamily) {
+            $this->updatedAt = new CarbonImmutable();
+            $this->portalLicenseFamily = $portalLicenseFamily;
+
+            $this->events[] = new Events\ApplicationInstallationPortalLicenseFamilyChangedEvent(
+                $this->id,
+                $this->updatedAt,
+                $this->portalLicenseFamily,
+                $portalLicenseFamily
+            );
+        }
+    }
+
+    #[\Override]
+    public function getPortalUsersCount(): ?int
+    {
+        return $this->portalUsersCount;
+    }
+
+    #[\Override]
+    public function changePortalUsersCount(int $usersCount): void
+    {
+        if ($usersCount < 0) {
+            throw new \InvalidArgumentException('Users count can not be negative');
+        }
+
+        if ($this->portalUsersCount !== $usersCount) {
+            $this->portalUsersCount = $usersCount;
+            $this->updatedAt = new CarbonImmutable();
+
+            $this->events[] = new Events\ApplicationInstallationPortalUsersCountChangedEvent(
+                $this->id,
+                $this->updatedAt,
+                $this->portalUsersCount,
+                $usersCount
+            );
+        }
+    }
+
+    #[\Override]
+    public function getComment(): ?string
+    {
+        return $this->comment;
+    }
+
+    #[\Override]
+    public function isApplicationTokenValid(string $applicationToken): bool
+    {
+        return $this->applicationToken === $applicationToken;
+    }
+
+    #[\Override]
+    public function setApplicationToken(string $applicationToken): void
+    {
+        $this->guardEmptyToken($applicationToken);
+
+        $this->updatedAt = new CarbonImmutable();
+        $this->applicationToken = $applicationToken;
+    }
+
+    #[\Override]
+    public function linkContactPerson(Uuid $uuid): void
+    {
+        $this->updatedAt = new CarbonImmutable();
+        $this->contactPersonId = $uuid;
+
+        $this->events[] = new ApplicationInstallationContactPersonLinkedEvent(
+            $this->id,
+            $this->updatedAt,
+            $this->contactPersonId
+        );
+    }
+
+    #[\Override]
+    public function unlinkContactPerson(): void
+    {
+        $this->updatedAt = new CarbonImmutable();
+
+        $this->events[] = new Events\ApplicationInstallationContactPersonUnlinkedEvent(
+            $this->id,
+            $this->updatedAt,
+            $this->contactPersonId
+        );
+
+        $this->contactPersonId = null;
+    }
+
+    #[\Override]
+    public function linkBitrix24PartnerContactPerson(Uuid $uuid): void
+    {
+        $this->updatedAt = new CarbonImmutable();
+        $this->bitrix24PartnerContactPersonId = $uuid;
+
+        $this->events[] = new Events\ApplicationInstallationBitrix24PartnerContactPersonLinkedEvent(
+            $this->id,
+            $this->updatedAt,
+            $this->bitrix24PartnerContactPersonId
+        );
+    }
+
+    #[\Override]
+    public function unlinkBitrix24PartnerContactPerson(): void
+    {
+        $this->updatedAt = new CarbonImmutable();
+
+        $this->events[] = new Events\ApplicationInstallationBitrix24PartnerContactPersonUnlinkedEvent(
+            $this->id,
+            $this->updatedAt,
+            $this->bitrix24PartnerContactPersonId
+        );
+
+        $this->bitrix24PartnerContactPersonId = null;
+    }
+
+    #[\Override]
+    public function linkBitrix24Partner(Uuid $uuid): void
+    {
+        $this->updatedAt = new CarbonImmutable();
+        $this->bitrix24PartnerId = $uuid;
+
+        $this->events[] = new Events\ApplicationInstallationBitrix24PartnerLinkedEvent(
+            $this->id,
+            $this->updatedAt,
+            $this->bitrix24PartnerId
+        );
+    }
+
+    #[\Override]
+    public function unlinkBitrix24Partner(): void
+    {
+        $this->updatedAt = new CarbonImmutable();
+
+        $this->events[] = new Events\ApplicationInstallationBitrix24PartnerUnlinkedEvent(
+            $this->id,
+            $this->updatedAt,
+            $this->bitrix24PartnerId
+        );
+
+        $this->bitrix24PartnerId = null;
+    }
+
+    private function addApplicationCreatedEventIfNeeded(bool $isEmitCreatedEvent): void
+    {
+        if ($isEmitCreatedEvent) {
+            // Создание события и добавление его в массив событий
+            $this->events[] = new ApplicationInstallationCreatedEvent(
+                $this->id,
+                $this->createdAt,
+                $this->bitrix24AccountId
+            );
+        }
+    }
+
+    private function guardTokenMismatch(string $applicationToken): void
+    {
+        if (!$this->isApplicationTokenValid($applicationToken)) {
+            throw new InvalidArgumentException(
+                sprintf(
+                    'application token «%s» mismatch with application token «%s» for application installation «%s»',
+                    $applicationToken,
+                    $this->applicationToken,
+                    $this->id->toRfc4122()
+                )
+            );
+        }
+    }
+
+    private function guardEmptyToken(string $applicationToken): void
+    {
+        if ('' === $applicationToken) {
+            throw new InvalidArgumentException('application token cannot be empty');
+        }
+    }
+}
diff --git a/src/ApplicationInstallations/Infrastructure/Doctrine/ApplicationInstallationRepository.php b/src/ApplicationInstallations/Infrastructure/Doctrine/ApplicationInstallationRepository.php
new file mode 100644
index 0000000..df950b4
--- /dev/null
+++ b/src/ApplicationInstallations/Infrastructure/Doctrine/ApplicationInstallationRepository.php
@@ -0,0 +1,165 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Bitrix24\Lib\ApplicationInstallations\Infrastructure\Doctrine;
+
+use Bitrix24\Lib\ApplicationInstallations\Entity\ApplicationInstallation;
+use Bitrix24\Lib\Bitrix24Accounts\Entity\Bitrix24Account;
+use Bitrix24\SDK\Application\Contracts\ApplicationInstallations\Entity\ApplicationInstallationInterface;
+use Bitrix24\SDK\Application\Contracts\ApplicationInstallations\Entity\ApplicationInstallationStatus;
+use Bitrix24\SDK\Application\Contracts\ApplicationInstallations\Exceptions\ApplicationInstallationNotFoundException;
+use Bitrix24\SDK\Application\Contracts\ApplicationInstallations\Repository\ApplicationInstallationRepositoryInterface;
+use Bitrix24\SDK\Core\Exceptions\InvalidArgumentException;
+use Doctrine\ORM\EntityManagerInterface;
+use Doctrine\ORM\EntityRepository;
+use Doctrine\ORM\Query\Expr\Join;
+use Symfony\Component\Uid\Uuid;
+
+class ApplicationInstallationRepository extends EntityRepository implements ApplicationInstallationRepositoryInterface
+{
+    public function __construct(EntityManagerInterface $entityManager)
+    {
+        parent::__construct($entityManager, $entityManager->getClassMetadata(ApplicationInstallation::class));
+    }
+
+    #[\Override]
+    public function save(ApplicationInstallationInterface $applicationInstallation): void
+    {
+        $this->getEntityManager()->persist($applicationInstallation);
+    }
+
+    #[\Override]
+    public function getById(Uuid $uuid): ApplicationInstallationInterface
+    {
+        $applicationInstallation = $this->getEntityManager()->getRepository(ApplicationInstallation::class)
+            ->createQueryBuilder('appInstallation')
+            ->where('appInstallation.id = :uuid')
+            ->andWhere('appInstallation.status != :status')
+            ->setParameter('uuid', $uuid)
+            ->setParameter('status', ApplicationInstallationStatus::deleted)
+            ->getQuery()
+            ->getOneOrNullResult()
+        ;
+
+        if (null === $applicationInstallation) {
+            throw new ApplicationInstallationNotFoundException(
+                sprintf('application installed not found by id %s', $uuid->toRfc4122())
+            );
+        }
+
+        return $applicationInstallation;
+    }
+
+    #[\Override]
+    public function delete(Uuid $uuid): void
+    {
+        $applicationInstallation = $this->getEntityManager()->getRepository(ApplicationInstallation::class)->find($uuid);
+
+        if (null == $applicationInstallation) {
+            throw new ApplicationInstallationNotFoundException(
+                sprintf('Application installation with uuid %s not found', $uuid->toRfc4122())
+            );
+        }
+
+        if (ApplicationInstallationStatus::deleted !== $applicationInstallation->getStatus()) {
+            throw new InvalidArgumentException(
+                sprintf('you cannot delete application installed because you status must be deleted your status %s', $applicationInstallation->getStatus()->name)
+            );
+        }
+
+        $this->save($applicationInstallation);
+    }
+
+    #[\Override]
+    // У нас в установке аккаунтId это констрейнт, так что возращать мы должны сущность.
+    public function findByBitrix24AccountId(Uuid $uuid): ?ApplicationInstallationInterface
+    {
+        return $this->getEntityManager()->getRepository(ApplicationInstallation::class)
+            ->createQueryBuilder('appInstallation')
+            ->where('appInstallation.bitrix24AccountId = :bitrix24AccountId')
+            ->orderBy('appInstallation.createdAt', 'DESC')
+            ->setParameter('bitrix24AccountId', $uuid)
+            ->getQuery()
+            ->getOneOrNullResult()
+        ;
+    }
+
+    #[\Override]
+    public function findByExternalId(string $externalId): array
+    {
+        if ('' === trim($externalId)) {
+            throw new InvalidArgumentException('external id cannot be empty');
+        }
+
+        return $this->getEntityManager()->getRepository(ApplicationInstallation::class)
+            ->createQueryBuilder('appInstallation')
+            ->where('appInstallation.externalId = :externalId')
+            ->orderBy('appInstallation.createdAt', 'DESC')
+            ->setParameter('externalId', $externalId)
+            ->getQuery()
+            ->getResult()
+        ;
+    }
+
+    public function findActiveByAccountId(Uuid $uuid): ?ApplicationInstallationInterface
+    {
+        $activeStatuses = [
+            ApplicationInstallationStatus::new,
+            ApplicationInstallationStatus::active,
+        ];
+
+        return $this->getEntityManager()->getRepository(ApplicationInstallation::class)
+            ->createQueryBuilder('applicationInstallation')
+            ->where('applicationInstallation.bitrix24AccountId = :b24AccountId')
+            ->andWhere('applicationInstallation.status IN (:statuses)')
+            ->setParameter('b24AccountId', $uuid)
+            ->setParameter('statuses', $activeStatuses)
+            ->getQuery()
+            ->getOneOrNullResult()
+        ;
+    }
+
+    public function findActiveByApplicationToken(string $applicationToken): ?ApplicationInstallationInterface
+    {
+        $activeStatuses = [
+            ApplicationInstallationStatus::new,
+            ApplicationInstallationStatus::active,
+        ];
+
+        return $this->getEntityManager()->getRepository(ApplicationInstallation::class)
+            ->createQueryBuilder('applicationInstallation')
+            ->where('applicationInstallation.applicationToken = :applicationToken')
+            ->andWhere('applicationInstallation.status IN (:statuses)')
+            ->setParameter('applicationToken', $applicationToken)
+            ->setParameter('statuses', $activeStatuses)
+            ->getQuery()
+            ->getOneOrNullResult()
+        ;
+    }
+
+    /**
+     * Получаем активную установку приложения с помощью аккаунта.
+     *
+     * @return null|ApplicationInstallation
+     */
+    public function findActiveInstallationWithAccountByMemberId(string $memberId): ?ApplicationInstallationInterface
+    {
+        $queryBuilder = $this->createQueryBuilder('ai');
+
+        return $queryBuilder->leftJoin(
+            Bitrix24Account::class,
+            'b24',
+            Join::WITH,
+            'ai.bitrix24AccountId = b24.id AND b24.isMasterAccount = true'
+        )
+            ->where('b24.memberId = :memberId')
+            ->andWhere('b24.isMasterAccount = true')
+            ->andWhere('ai.status != :status')
+            ->setParameter('memberId', $memberId)
+            ->setParameter('status', ApplicationInstallationStatus::deleted)
+            ->getQuery()
+            ->getOneOrNullResult()
+        ;
+    }
+}
diff --git a/src/ApplicationInstallations/UseCase/Install/Command.php b/src/ApplicationInstallations/UseCase/Install/Command.php
new file mode 100644
index 0000000..120f803
--- /dev/null
+++ b/src/ApplicationInstallations/UseCase/Install/Command.php
@@ -0,0 +1,84 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Bitrix24\Lib\ApplicationInstallations\UseCase\Install;
+
+use Bitrix24\Lib\Bitrix24Accounts\ValueObjects\Domain;
+use Bitrix24\SDK\Application\ApplicationStatus;
+use Bitrix24\SDK\Application\PortalLicenseFamily;
+use Bitrix24\SDK\Core\Credentials\AuthToken;
+use Bitrix24\SDK\Core\Credentials\Scope;
+use Bitrix24\SDK\Core\Exceptions\InvalidArgumentException;
+use Symfony\Component\Uid\Uuid;
+
+/**
+ * Установка может происходить по 2 сценриям.
+ * Если в эту команду передается $applicationToken значит это установка без UI.
+ * Иначе это установка с UI и $applicationToken передаваться не должен.
+ *
+ * 1) UI - Пользователь запускает установку через интерфейс.
+ * Bitrix24 отправляет первичный запрос на /install.php с параметрами:
+ * AUTH_ID, REFRESH_ID, member_id в теле запроса. Без application_token
+ * Система создаёт Bitrix24Account в статусе new.
+ * Bitrix24 отправляет событие ONAPPINSTALL на /event-handler.php и передает application_token
+ * Вызывается applicationInstalled($applicationToken) с полученным токеном.
+ * 2) Без UI - Установка инициируется прямым POST-запросом с полным набором credentials.
+ * Сразу создается Bitrix24Account. У установщика и у аккаунта вызывается метод с переданыым токеном:
+ * $bitrix24Account->applicationInstalled($applicationToken);
+ * $applicationInstallation->applicationInstalled($applicationToken);.
+ */
+readonly class Command
+{
+    public function __construct(
+        public ApplicationStatus $applicationStatus,
+        public PortalLicenseFamily $portalLicenseFamily,
+        public ?int $portalUsersCount,
+        public ?Uuid $contactPersonId,
+        public ?Uuid $bitrix24PartnerContactPersonId,
+        public ?Uuid $bitrix24PartnerId,
+        public ?string $externalId,
+        public ?string $comment,
+        public int $bitrix24UserId,
+        public bool $isBitrix24UserAdmin,
+        public string $memberId,
+        public Domain $domain,
+        public AuthToken $authToken,
+        public int $applicationVersion,
+        public Scope $applicationScope,
+        public ?string $applicationToken = null,
+    ) {
+        $this->validate();
+    }
+
+    private function validate(): void
+    {
+        if ($this->portalUsersCount <= 0) {
+            throw new InvalidArgumentException('Portal Users count must be a positive integer.');
+        }
+
+        if ('' === $this->externalId) {
+            throw new InvalidArgumentException('External ID must be a non-empty string.');
+        }
+
+        if ('' === $this->comment) {
+            throw new InvalidArgumentException('Comment must be a non-empty string.');
+        }
+
+        if ($this->bitrix24UserId <= 0) {
+            throw new InvalidArgumentException('Bitrix24 User ID must be a positive integer.');
+        }
+
+        if ('' === $this->memberId) {
+            throw new InvalidArgumentException('Member ID must be a non-empty string.');
+        }
+
+        if ($this->applicationVersion <= 0) {
+            throw new InvalidArgumentException('Application version must be a positive integer.');
+        }
+
+        if (null !== $this->applicationToken && '' === trim($this->applicationToken)) {
+            throw new InvalidArgumentException('Application token must be a non-empty string.');
+        }
+    }
+}
diff --git a/src/ApplicationInstallations/UseCase/Install/Handler.php b/src/ApplicationInstallations/UseCase/Install/Handler.php
new file mode 100644
index 0000000..1000e54
--- /dev/null
+++ b/src/ApplicationInstallations/UseCase/Install/Handler.php
@@ -0,0 +1,124 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Bitrix24\Lib\ApplicationInstallations\UseCase\Install;
+
+use Bitrix24\Lib\ApplicationInstallations\Entity\ApplicationInstallation;
+use Bitrix24\Lib\ApplicationInstallations\Infrastructure\Doctrine\ApplicationInstallationRepository;
+use Bitrix24\Lib\Bitrix24Accounts\Entity\Bitrix24Account;
+use Bitrix24\Lib\Bitrix24Accounts\Infrastructure\Doctrine\Bitrix24AccountRepository;
+use Bitrix24\Lib\Services\Flusher;
+use Bitrix24\SDK\Application\Contracts\ApplicationInstallations\Entity\ApplicationInstallationInterface;
+use Bitrix24\SDK\Application\Contracts\Bitrix24Accounts\Entity\Bitrix24AccountInterface;
+use Bitrix24\SDK\Application\Contracts\Events\AggregateRootEventsEmitterInterface;
+use Bitrix24\SDK\Core\Exceptions\InvalidArgumentException;
+use Psr\Log\LoggerInterface;
+use Symfony\Component\Uid\Uuid;
+
+readonly class Handler
+{
+    public function __construct(
+        private Bitrix24AccountRepository $bitrix24AccountRepository,
+        private ApplicationInstallationRepository $applicationInstallationRepository,
+        private Flusher $flusher,
+        private LoggerInterface $logger
+    ) {}
+
+    /**
+     * На данный момент могут быть не обработаны несколько сценариев.
+     * Например :
+     * 1) По какой-то причине мы пропустили событие от Б24 с токеном, о том, что надо удалить приложение (удален портал, мы были не доступны и запрос пропущен или еще как-то)
+     * 2) Надо вручную или еще как-то удалить приложение зная только его member_id (может что-то еще для валидации).
+     *
+     * @throws InvalidArgumentException
+     */
+    public function handle(Command $command): void
+    {
+        $this->logger->info('ApplicationInstallations.Install.start', [
+            'externalId' => $command->externalId,
+            'bitrix24UserId' => $command->bitrix24UserId,
+            'isBitrix24UserAdmin' => $command->isBitrix24UserAdmin,
+            'memberId' => $command->memberId,
+            'applicationToken' => $command->applicationToken,
+        ]);
+
+        /** @var null|AggregateRootEventsEmitterInterface|ApplicationInstallationInterface $activeInstallation */
+        $activeInstallation = $this->applicationInstallationRepository->findActiveInstallationWithAccountByMemberId($command->memberId);
+
+        if (null !== $activeInstallation) {
+            $entitiesToFlush = [];
+
+            $activeInstallation->applicationUninstalled();
+
+            $this->applicationInstallationRepository->save($activeInstallation);
+
+            $entitiesToFlush[] = $activeInstallation;
+
+            /** @var AggregateRootEventsEmitterInterface|Bitrix24AccountInterface[] $b24Accounts */
+            $b24Accounts = $this->bitrix24AccountRepository->findByMemberId($command->memberId);
+
+            if ([] !== $b24Accounts) {
+                foreach ($b24Accounts as $b24Account) {
+                    $b24Account->applicationUninstalled(null);
+                    $this->bitrix24AccountRepository->save($b24Account);
+                    $entitiesToFlush[] = $b24Account;
+                }
+            }
+
+            /*
+            Здесь сразу флашим так как это условие не всегда работает , и лучше сначало разобраться с аккаунтами и установщиками
+            которые нужно деактивировать , а после уже работаем с новыми сущностями.
+           */
+            $this->flusher->flush(...$entitiesToFlush);
+        }
+
+        $uuidV7 = Uuid::v7();
+        $applicationInstallationId = Uuid::v7();
+
+        $bitrix24Account = new Bitrix24Account(
+            $uuidV7,
+            $command->bitrix24UserId,
+            $command->isBitrix24UserAdmin,
+            $command->memberId,
+            $command->domain->value,
+            $command->authToken,
+            $command->applicationVersion,
+            $command->applicationScope,
+            true,
+            true
+        );
+
+        $bitrix24Account->applicationInstalled($command->applicationToken);
+
+        $this->bitrix24AccountRepository->save($bitrix24Account);
+
+        $applicationInstallation = new ApplicationInstallation(
+            $applicationInstallationId,
+            $uuidV7,
+            $command->applicationStatus,
+            $command->portalLicenseFamily,
+            $command->portalUsersCount,
+            $command->contactPersonId,
+            $command->bitrix24PartnerContactPersonId,
+            $command->bitrix24PartnerId,
+            $command->externalId,
+            $command->comment,
+            true
+        );
+
+        $applicationInstallation->applicationInstalled($command->applicationToken);
+
+        $this->applicationInstallationRepository->save($applicationInstallation);
+
+        $this->flusher->flush($applicationInstallation, $bitrix24Account);
+
+        $this->logger->info(
+            'ApplicationInstallations.Install.Finish',
+            [
+                'applicationId' => $applicationInstallationId,
+                'bitrix24AccountId' => $uuidV7,
+            ]
+        );
+    }
+}
diff --git a/src/ApplicationInstallations/UseCase/OnAppInstall/Command.php b/src/ApplicationInstallations/UseCase/OnAppInstall/Command.php
new file mode 100644
index 0000000..2658e2f
--- /dev/null
+++ b/src/ApplicationInstallations/UseCase/OnAppInstall/Command.php
@@ -0,0 +1,39 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Bitrix24\Lib\ApplicationInstallations\UseCase\OnAppInstall;
+
+use Bitrix24\Lib\Bitrix24Accounts\ValueObjects\Domain;
+
+/**
+ * Команда вызывается в тех случаях если установка происходит с помощью UI.
+ * Bitrix24 отправляет событие ONAPPINSTALL на /event-handler.php и передает application_token.
+ * Цель этого события донести токен приложения.
+ */
+readonly class Command
+{
+    public function __construct(
+        public string $memberId,
+        public Domain $domainUrl,
+        public string $applicationToken,
+        public string $applicationStatus,
+    ) {
+        $this->validate();
+    }
+
+    private function validate(): void
+    {
+        if ('' === $this->memberId) {
+            throw new \InvalidArgumentException('Member ID must be a non-empty string.');
+        }
+
+        if ('' === $this->applicationToken) {
+            throw new \InvalidArgumentException('ApplicationToken must be a non-empty string.');
+        }
+
+        if ('' === $this->applicationStatus) {
+            throw new \InvalidArgumentException('ApplicationStatus must be a non-empty string.');
+        }
+    }
+}
diff --git a/src/ApplicationInstallations/UseCase/OnAppInstall/Handler.php b/src/ApplicationInstallations/UseCase/OnAppInstall/Handler.php
new file mode 100644
index 0000000..667a5c2
--- /dev/null
+++ b/src/ApplicationInstallations/UseCase/OnAppInstall/Handler.php
@@ -0,0 +1,64 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Bitrix24\Lib\ApplicationInstallations\UseCase\OnAppInstall;
+
+use Bitrix24\Lib\ApplicationInstallations\Infrastructure\Doctrine\ApplicationInstallationRepository;
+use Bitrix24\Lib\Bitrix24Accounts\Infrastructure\Doctrine\Bitrix24AccountRepository;
+use Bitrix24\Lib\Services\Flusher;
+use Bitrix24\SDK\Application\ApplicationStatus;
+use Bitrix24\SDK\Application\Contracts\ApplicationInstallations\Entity\ApplicationInstallationInterface;
+use Bitrix24\SDK\Application\Contracts\Bitrix24Accounts\Entity\Bitrix24AccountInterface;
+use Bitrix24\SDK\Application\Contracts\Bitrix24Accounts\Entity\Bitrix24AccountStatus;
+use Bitrix24\SDK\Application\Contracts\Events\AggregateRootEventsEmitterInterface;
+use Bitrix24\SDK\Core\Exceptions\InvalidArgumentException;
+use Psr\Log\LoggerInterface;
+
+readonly class Handler
+{
+    public function __construct(
+        private Bitrix24AccountRepository $bitrix24AccountRepository,
+        private ApplicationInstallationRepository $applicationInstallationRepository,
+        private Flusher $flusher,
+        private LoggerInterface $logger
+    ) {}
+
+    /**
+     * @throws InvalidArgumentException
+     */
+    public function handle(Command $command): void
+    {
+        $this->logger->info('ApplicationInstallation.OnAppInstall.start', [
+            'b24_domain_url' => $command->domainUrl,
+            'b24_member_id' => $command->memberId,
+            'b24_application_id' => $command->applicationToken,
+            'application_status' => $command->applicationStatus,
+        ]);
+
+        /** @var null|AggregateRootEventsEmitterInterface|ApplicationInstallationInterface $applicationInstallation */
+        $applicationInstallation = $this->applicationInstallationRepository->findActiveInstallationWithAccountByMemberId($command->memberId);
+
+        $applicationStatus = new ApplicationStatus($command->applicationStatus);
+
+        $applicationInstallation->changeApplicationStatus($applicationStatus);
+
+        $applicationInstallation->setApplicationToken($command->applicationToken);
+
+        $this->applicationInstallationRepository->save($applicationInstallation);
+
+        /** @var AggregateRootEventsEmitterInterface|Bitrix24AccountInterface $bitrix24Account */
+        $bitrix24Account = $this->bitrix24AccountRepository->findMasterByMemberId(
+            $command->memberId,
+            Bitrix24AccountStatus::active,
+        );
+
+        $bitrix24Account->setApplicationToken($command->applicationToken);
+
+        $this->bitrix24AccountRepository->save($bitrix24Account);
+
+        $this->flusher->flush($applicationInstallation, $bitrix24Account);
+
+        $this->logger->info('ApplicationInstallation.OnAppInstall.finish');
+    }
+}
diff --git a/src/ApplicationInstallations/UseCase/Uninstall/Command.php b/src/ApplicationInstallations/UseCase/Uninstall/Command.php
new file mode 100644
index 0000000..84debaa
--- /dev/null
+++ b/src/ApplicationInstallations/UseCase/Uninstall/Command.php
@@ -0,0 +1,29 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Bitrix24\Lib\ApplicationInstallations\UseCase\Uninstall;
+
+use Bitrix24\Lib\Bitrix24Accounts\ValueObjects\Domain;
+
+readonly class Command
+{
+    public function __construct(
+        public Domain $domainUrl,
+        public string $memberId,
+        public string $applicationToken
+    ) {
+        $this->validate();
+    }
+
+    private function validate(): void
+    {
+        if ('' === $this->applicationToken) {
+            throw new \InvalidArgumentException('applicationToken must be a non-empty string.');
+        }
+
+        if ('' === $this->memberId) {
+            throw new \InvalidArgumentException('Member ID must be a non-empty string.');
+        }
+    }
+}
diff --git a/src/ApplicationInstallations/UseCase/Uninstall/Handler.php b/src/ApplicationInstallations/UseCase/Uninstall/Handler.php
new file mode 100644
index 0000000..273c2ba
--- /dev/null
+++ b/src/ApplicationInstallations/UseCase/Uninstall/Handler.php
@@ -0,0 +1,92 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Bitrix24\Lib\ApplicationInstallations\UseCase\Uninstall;
+
+use Bitrix24\Lib\ApplicationInstallations\Infrastructure\Doctrine\ApplicationInstallationRepository;
+use Bitrix24\Lib\Bitrix24Accounts\Infrastructure\Doctrine\Bitrix24AccountRepository;
+use Bitrix24\Lib\Services\Flusher;
+use Bitrix24\SDK\Application\Contracts\ApplicationInstallations\Entity\ApplicationInstallationInterface;
+use Bitrix24\SDK\Application\Contracts\Bitrix24Accounts\Entity\Bitrix24AccountInterface;
+use Bitrix24\SDK\Application\Contracts\Events\AggregateRootEventsEmitterInterface;
+use Psr\Log\LoggerInterface;
+
+/**
+ * Обработчик сценария деинсталляции приложения.
+ *
+ * Важно: Сценарий рассчитан на идеальные условия и может не учитывать случаи, когда:
+ * 1) В базе данных кто-то вручную удалил или деактивировал запись о деинсталляции, а затем вызвал этот обработчик.
+ * 2) Токен удаления поступает с задержкой (например, при быстрой установке и удалении приложения).
+ * 3) В системе может существовать несколько аккаунтов, однако деинсталляция на портале выполняется только один раз.
+ * 4) Для остальных аккаунтов деинсталляция невозможна — они используются только для авторизации и доступа.
+ *
+ * Возможные ограничения:
+ * 1) Если установка приложения производилась по событию, которое не произошло, токен может не сохраниться, что приведет к спорным ситуациям при деинсталляции.
+ * 2) Используйте этот обработчик только при уверенности в целостности данных и корректности порядка событий.
+ */
+readonly class Handler
+{
+    public function __construct(
+        private Bitrix24AccountRepository $bitrix24AccountRepository,
+        private ApplicationInstallationRepository $applicationInstallationRepository,
+        private Flusher $flusher,
+        private LoggerInterface $logger
+    ) {}
+
+    public function handle(Command $command): void
+    {
+        $this->logger->info('ApplicationInstallations.Uninstall.start', [
+            'domainUrl' => $command->domainUrl,
+            'memberId' => $command->memberId,
+            'applicationToken' => $command->applicationToken,
+        ]);
+
+        /** @var AggregateRootEventsEmitterInterface|ApplicationInstallationInterface $activeInstallation */
+        $activeInstallation = $this->applicationInstallationRepository->findActiveByApplicationToken($command->applicationToken);
+
+        if (null !== $activeInstallation) {
+            $this->logger->info(
+                'ApplicationInstallations.Uninstall.Start'
+            );
+
+            $entitiesToFlush = [];
+
+            $activeInstallation->applicationUninstalled($command->applicationToken);
+
+            $this->applicationInstallationRepository->save($activeInstallation);
+
+            $entitiesToFlush[] = $activeInstallation;
+
+            /** @var AggregateRootEventsEmitterInterface|Bitrix24AccountInterface[] $b24Accounts */
+            $b24Accounts = $this->bitrix24AccountRepository->findByMemberId($command->memberId);
+
+            if ([] !== $b24Accounts) {
+                foreach ($b24Accounts as $b24Account) {
+                    $b24Account->applicationUninstalled(null);
+                    $this->bitrix24AccountRepository->save($b24Account);
+                    $entitiesToFlush[] = $b24Account;
+                }
+            }
+
+            $this->flusher->flush(...$entitiesToFlush);
+
+            $this->logger->info('ApplicationInstallations.Uninstall.completed', [
+                'installationId' => $activeInstallation->getId(),
+                'applicationToken' => $command->applicationToken,
+                'flushedEntitiesCount' => count($entitiesToFlush),
+            ]);
+        } else {
+            $this->logger->info('ApplicationInstallations.Uninstall.false_request', [
+                'applicationToken' => $command->applicationToken,
+                'memberId' => $command->memberId,
+                'domainUrl' => $command->domainUrl,
+                'message' => 'No active installation found for uninstall request',
+            ]);
+        }
+
+        $this->logger->info(
+            'ApplicationInstallations.Uninstall.Finish'
+        );
+    }
+}
diff --git a/src/Bitrix24Accounts/Entity/Bitrix24Account.php b/src/Bitrix24Accounts/Entity/Bitrix24Account.php
index 616f75d..ec1f651 100644
--- a/src/Bitrix24Accounts/Entity/Bitrix24Account.php
+++ b/src/Bitrix24Accounts/Entity/Bitrix24Account.php
@@ -33,7 +33,11 @@ class Bitrix24Account extends AggregateRoot implements Bitrix24AccountInterface
 {
     private ?string $applicationToken = null;
 
-    private ?string $comment = null;
+    private readonly CarbonImmutable $createdAt;
+
+    private CarbonImmutable $updatedAt;
+
+    private Bitrix24AccountStatus $status = Bitrix24AccountStatus::new;
 
     public function __construct(
         private readonly Uuid $id,
@@ -42,15 +46,16 @@ public function __construct(
         /** bitrix24 portal unique id */
         private readonly string $memberId,
         private string $domainUrl,
-        private Bitrix24AccountStatus $status,
         private AuthToken $authToken,
-        private readonly CarbonImmutable $createdAt,
-        private CarbonImmutable $updatedAt,
         private int $applicationVersion,
         private Scope $applicationScope,
-        bool $isEmitBitrix24AccountCreatedEvent = false,
+        private readonly bool $isMasterAccount = false,
+        private $isEmitBitrix24AccountCreatedEvent = false,
+        private ?string $comment = null
     ) {
-        $this->addAccountCreatedEventIfNeeded($isEmitBitrix24AccountCreatedEvent);
+        $this->createdAt = new CarbonImmutable();
+        $this->updatedAt = new CarbonImmutable();
+        $this->addAccountCreatedEventIfNeeded($this->isEmitBitrix24AccountCreatedEvent);
     }
 
     #[\Override]
@@ -170,7 +175,7 @@ public function changeDomainUrl(string $newDomainUrl): void
      * @throws InvalidArgumentException
      */
     #[\Override]
-    public function applicationInstalled(string $applicationToken): void
+    public function applicationInstalled(?string $applicationToken): void
     {
         if (Bitrix24AccountStatus::new !== $this->status) {
             throw new InvalidArgumentException(
@@ -181,12 +186,12 @@ public function applicationInstalled(string $applicationToken): void
             );
         }
 
-        if ('' === $applicationToken) {
-            throw new InvalidArgumentException('application token cannot be empty');
+        if (null !== $applicationToken) {
+            $this->guardEmptyToken($applicationToken);
+            $this->applicationToken = $applicationToken;
         }
 
         $this->status = Bitrix24AccountStatus::active;
-        $this->applicationToken = $applicationToken;
         $this->updatedAt = new CarbonImmutable();
         $this->events[] = new Bitrix24AccountApplicationInstalledEvent(
             $this->id,
@@ -194,21 +199,25 @@ public function applicationInstalled(string $applicationToken): void
         );
     }
 
-    /**
-     * @throws InvalidArgumentException
-     */
     #[\Override]
-    public function applicationUninstalled(string $applicationToken): void
+    public function applicationUninstalled(?string $applicationToken): void
     {
-        $this->guardEmptyToken($applicationToken);
-        $this->guardTokenMismatch($applicationToken);
-        $this->guardApplicationIsActive();
-        $this->status = Bitrix24AccountStatus::deleted;
-        $this->updatedAt = new CarbonImmutable();
-        $this->events[] = new Bitrix24AccountApplicationUninstalledEvent(
-            $this->id,
-            new CarbonImmutable()
-        );
+        if (
+            Bitrix24AccountStatus::new == $this->status
+            || Bitrix24AccountStatus::active == $this->status
+        ) {
+            if (null !== $applicationToken) {
+                $this->guardEmptyToken($applicationToken);
+                $this->guardTokenMismatch($applicationToken);
+            }
+
+            $this->status = Bitrix24AccountStatus::deleted;
+            $this->updatedAt = new CarbonImmutable();
+            $this->events[] = new Bitrix24AccountApplicationUninstalledEvent(
+                $this->id,
+                new CarbonImmutable()
+            );
+        }
     }
 
     #[\Override]
@@ -283,6 +292,21 @@ public function markAsActive(?string $comment): void
         $this->updatedAt = new CarbonImmutable();
     }
 
+    #[\Override]
+    public function isMasterAccount(): bool
+    {
+        return $this->isMasterAccount;
+    }
+
+    #[\Override]
+    public function setApplicationToken(string $applicationToken): void
+    {
+        $this->guardEmptyToken($applicationToken);
+
+        $this->updatedAt = new CarbonImmutable();
+        $this->applicationToken = $applicationToken;
+    }
+
     /**
      * @throws InvalidArgumentException
      */
@@ -331,18 +355,6 @@ private function guardTokenMismatch(string $applicationToken): void
         }
     }
 
-    private function guardApplicationIsActive(): void
-    {
-        if (Bitrix24AccountStatus::active !== $this->status) {
-            throw new InvalidArgumentException(
-                sprintf(
-                    'for uninstall account must be in status «active», current status - «%s»',
-                    $this->status->name
-                )
-            );
-        }
-    }
-
     private function addAccountCreatedEventIfNeeded(bool $isEmitCreatedEvent): void
     {
         if ($isEmitCreatedEvent) {
diff --git a/src/Bitrix24Accounts/Infrastructure/Doctrine/Bitrix24AccountRepository.php b/src/Bitrix24Accounts/Infrastructure/Doctrine/Bitrix24AccountRepository.php
index 5fb37ad..6f71eae 100644
--- a/src/Bitrix24Accounts/Infrastructure/Doctrine/Bitrix24AccountRepository.php
+++ b/src/Bitrix24Accounts/Infrastructure/Doctrine/Bitrix24AccountRepository.php
@@ -56,6 +56,7 @@ public function existsById(Uuid $uuid): bool
             ->createQueryBuilder('b24')
             ->where('b24.id = :id')
             ->andWhere('b24.status != :status')
+            ->orderBy('b24.createdAt', 'DESC')
             ->setParameter('id', $uuid)
             ->setParameter('status', Bitrix24AccountStatus::deleted)
             ->getQuery()
@@ -105,6 +106,64 @@ public function findByMemberId(
         return $this->findBy($criteria);
     }
 
+    /**
+     * @phpstan-return Bitrix24AccountInterface|null
+     *
+     * @throws InvalidArgumentException
+     */
+    public function findMasterByMemberId(
+        string $memberId,
+        ?Bitrix24AccountStatus $bitrix24AccountStatus = null,
+        ?int $bitrix24UserId = null,
+        ?bool $isAdmin = null
+    ): ?Bitrix24AccountInterface {
+        if ('' === trim($memberId)) {
+            throw new InvalidArgumentException('memberId cannot be empty');
+        }
+
+        $criteria = [
+            'memberId' => $memberId,
+            'isMasterAccount' => true,
+        ];
+
+        if ($bitrix24AccountStatus instanceof Bitrix24AccountStatus) {
+            $criteria['status'] = $bitrix24AccountStatus->name;
+        }
+
+        if (null !== $bitrix24UserId) {
+            $criteria['bitrix24UserId'] = $bitrix24UserId;
+        }
+
+        if (null !== $isAdmin) {
+            $criteria['isBitrix24UserAdmin'] = $isAdmin;
+        }
+
+        return $this->findOneBy($criteria);
+    }
+
+    public function findActiveByMemberId(string $memberId): array
+    {
+        if ('' === trim($memberId)) {
+            throw new InvalidArgumentException('memberId cannot be empty');
+        }
+
+        $activeStatuses = [
+            Bitrix24AccountStatus::new,
+            Bitrix24AccountStatus::active,
+        ];
+
+        return $this->getEntityManager()->getRepository(Bitrix24Account::class)
+            ->createQueryBuilder('b24')
+            ->where('b24.memberId = :memberId')
+            ->andWhere('b24.status IN (:statuses)')
+            ->orderBy('b24.createdAt', 'DESC')
+            ->setParameter('memberId', $memberId)
+            ->setParameter('statuses', $activeStatuses)
+            ->getQuery()
+            ->getResult()
+        ;
+    }
+
     #[\Override]
     public function delete(Uuid $uuid): void
     {
@@ -163,9 +222,9 @@ public function findByApplicationToken(string $applicationToken): array
     }
 
     /**
-     * @throws InvalidArgumentException
-     *
      * @phpstan-return Bitrix24AccountInterface&AggregateRootEventsEmitterInterface
+     *
+     * @throws InvalidArgumentException
      */
     #[\Override]
     public function findOneAdminByMemberId(string $memberId): ?Bitrix24AccountInterface
@@ -184,10 +243,10 @@ public function findOneAdminByMemberId(string $memberId): ?Bitrix24AccountInterf
     }
 
     /**
-     * @phpstan-return array<Bitrix24AccountInterface&AggregateRootEventsEmitterInterface>
-     *
      * @return array<AggregateRootEventsEmitterInterface&Bitrix24AccountInterface>
      *
+     * @phpstan-return array<Bitrix24AccountInterface&AggregateRootEventsEmitterInterface>
+     *
      * @throws InvalidArgumentException
      */
     #[\Override]
diff --git a/src/Bitrix24Accounts/UseCase/InstallFinish/Handler.php b/src/Bitrix24Accounts/UseCase/InstallFinish/Handler.php
index e5b805d..f8518cf 100644
--- a/src/Bitrix24Accounts/UseCase/InstallFinish/Handler.php
+++ b/src/Bitrix24Accounts/UseCase/InstallFinish/Handler.php
@@ -39,7 +39,7 @@ public function handle(Command $command): void
         /** @var AggregateRootEventsEmitterInterface|Bitrix24AccountInterface $bitrix24Account */
         $bitrix24Account = $this->getSingleAccountByMemberId($command->domain->value, $command->memberId, $command->bitrix24UserId);
 
-        $bitrix24Account->applicationInstalled($command->applicationToken);
+        $bitrix24Account->applicationInstalled(null);
 
         $this->bitrix24AccountRepository->save($bitrix24Account);
         $this->flusher->flush($bitrix24Account);
@@ -49,7 +49,6 @@ public function handle(Command $command): void
             [
                 'b24_domain_url' => $command->domain,
                 'b24_member_id' => $command->memberId,
-                'b24_application_id' => $command->applicationToken,
                 'b24_user_id' => $command->bitrix24UserId,
             ]
         );
diff --git a/src/Bitrix24Accounts/UseCase/InstallStart/Handler.php b/src/Bitrix24Accounts/UseCase/InstallStart/Handler.php
index 01e7ee0..ece0c7d 100644
--- a/src/Bitrix24Accounts/UseCase/InstallStart/Handler.php
+++ b/src/Bitrix24Accounts/UseCase/InstallStart/Handler.php
@@ -6,10 +6,8 @@
 
 use Bitrix24\Lib\Bitrix24Accounts\Entity\Bitrix24Account;
 use Bitrix24\Lib\Services\Flusher;
-use Bitrix24\SDK\Application\Contracts\Bitrix24Accounts\Entity\Bitrix24AccountStatus;
 use Bitrix24\SDK\Application\Contracts\Bitrix24Accounts\Exceptions\Bitrix24AccountNotFoundException;
 use Bitrix24\SDK\Application\Contracts\Bitrix24Accounts\Repository\Bitrix24AccountRepositoryInterface;
-use Carbon\CarbonImmutable;
 use Psr\Log\LoggerInterface;
 
 readonly class Handler
@@ -34,12 +32,10 @@ public function handle(Command $command): void
             $command->isBitrix24UserAdmin,
             $command->memberId,
             $command->domain->value,
-            Bitrix24AccountStatus::new,
             $command->authToken,
-            new CarbonImmutable(),
-            new CarbonImmutable(),
             $command->applicationVersion,
             $command->applicationScope,
+            false,
             true
         );
 
diff --git a/src/Bitrix24Accounts/UseCase/Uninstall/Handler.php b/src/Bitrix24Accounts/UseCase/Uninstall/Handler.php
index 516126b..b2e0182 100644
--- a/src/Bitrix24Accounts/UseCase/Uninstall/Handler.php
+++ b/src/Bitrix24Accounts/UseCase/Uninstall/Handler.php
@@ -30,9 +30,10 @@ public function handle(Command $command): void
 
         /** @var AggregateRootEventsEmitterInterface[]|Bitrix24AccountInterface[] $accounts */
         $accounts = $this->bitrix24AccountRepository->findByApplicationToken($command->applicationToken);
+
         $accountsCount = count($accounts);
         foreach ($accounts as $account) {
-            $account->applicationUninstalled($command->applicationToken);
+            $account->applicationUninstalled(null);
             $this->bitrix24AccountRepository->save($account);
         }
 
diff --git a/src/Bitrix24Accounts/ValueObjects/Domain.php b/src/Bitrix24Accounts/ValueObjects/Domain.php
index a399ee7..e172b22 100644
--- a/src/Bitrix24Accounts/ValueObjects/Domain.php
+++ b/src/Bitrix24Accounts/ValueObjects/Domain.php
@@ -14,16 +14,44 @@ public function __construct(string $domain)
         $this->value = $domain;
     }
 
+    /*
+     * @return void
+     *
+     * Validates a domain name based on three main criteria:
+     * 1. **Allowed characters**:
+     *    - Latin, Cyrillic, digits, and hyphens.
+     *    - Hyphens are prohibited at the start/end of each label (regex: `$patternValidChars`).
+     *    - Supports IDN (Internationalized Domain Names).
+     * 2. **Overall domain length**:
+     *    - Not more than 255 characters (regex: `$patternLengthCheck`).
+     * 3. **Length of each label**:
+     *    - From 1 to 63 characters (regex: `$patternLengthEachLabel`).
+     *    - Maximum number of labels: 127 (as per RFC 1035).
+     *
+     * Complies with the requirements of:
+     * - RFC 1035 (basic domain name rules) [1].
+     * - RFC 5891 (IDN) [2].
+     *
+     * Examples of valid domains:
+     * - `example.com`
+     * - `кириллический-домен.рф`
+     *
+     * Composed of three patterns for simplicity and clarity.
+     * @throws \InvalidArgumentException If the domain fails any of the checks.
+     *
+     * [1] https://www.rfc-editor.org/rfc/rfc1035
+     * [2] https://www.rfc-editor.org/rfc/rfc5891
+     */
     private function validate(string $domain): void
     {
-        // Регулярное выражение для проверки допустимых символов (латиница и кириллица)
+        // Regular expression for checking available symbol (Latin and Cyrillic)
         $patternValidChars = '/^((?!-)[A-Za-zА-Яа-яЁё0-9-]{1,63}(?<!-)\.)+[A-Za-zА-Яа-яЁё]{2,6}$/u';
 
-        // Проверка общей длины (1-253 символа)
-        $patternLengthCheck = '/^.{1,253}$/';
+        // Checking summary length (1-255 symbols)
+        $patternLengthCheck = '/^.{1,255}$/';
 
-        // Проверка длины каждой метки (1-63 символа, включая кириллицу)
-        $patternLengthEachLabel = '/^[A-Za-zА-Яа-яЁё0-9-]{1,63}(\.[A-Za-zА-Яа-яЁё0-9-]{1,63})*$/u';
+        // Checking length each one label (1-63 symbol, include cyrillic)
+        $patternLengthEachLabel = '/^[A-Za-zА-Яа-яЁё0-9-]{1,63}(\.[A-Za-zА-Яа-яЁё0-9-]{1,63}){0,126}$/u';
         if (
             in_array(preg_match($patternValidChars, $domain), [0, false], true)
             || in_array(preg_match($patternLengthCheck, $domain), [0, false], true)
diff --git a/tests/Functional/ApplicationInstallations/Builders/ApplicationInstallationBuilder.php b/tests/Functional/ApplicationInstallations/Builders/ApplicationInstallationBuilder.php
new file mode 100644
index 0000000..264a03a
--- /dev/null
+++ b/tests/Functional/ApplicationInstallations/Builders/ApplicationInstallationBuilder.php
@@ -0,0 +1,119 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Bitrix24\Lib\Tests\Functional\ApplicationInstallations\Builders;
+
+use Bitrix24\Lib\ApplicationInstallations\Entity\ApplicationInstallation;
+use Bitrix24\SDK\Application\ApplicationStatus;
+use Bitrix24\SDK\Application\Contracts\ApplicationInstallations\Entity\ApplicationInstallationStatus;
+use Bitrix24\SDK\Application\PortalLicenseFamily;
+use Carbon\CarbonImmutable;
+use Symfony\Component\Uid\Uuid;
+
+class ApplicationInstallationBuilder
+{
+    private readonly Uuid $id;
+
+    private Uuid $bitrix24AccountId;
+
+    private readonly ?Uuid $contactPersonId;
+
+    private readonly ?Uuid $bitrix24PartnerContactPersonId;
+
+    private readonly ?Uuid $bitrix24PartnerId;
+
+    private ?string $externalId = null;
+
+    private ApplicationInstallationStatus $status;
+
+    private ApplicationStatus $applicationStatus;
+
+    private PortalLicenseFamily $portalLicenseFamily;
+
+    private readonly ?int $portalUsersCount;
+
+    private ?string $comment = null;
+
+    private ?string $applicationToken = null;
+
+    public function __construct()
+    {
+        $this->id = Uuid::v7();
+        $this->bitrix24AccountId = Uuid::v7();
+        $this->bitrix24PartnerContactPersonId = Uuid::v7();
+        $this->contactPersonId = Uuid::v7();
+        $this->bitrix24PartnerId = Uuid::v7();
+        $this->portalUsersCount = random_int(1, 1_000_000);
+    }
+
+    public function withExternalId(string $externalId): self
+    {
+        $this->externalId = $externalId;
+
+        return $this;
+    }
+
+    public function withApplicationToken(string $applicationToken): self
+    {
+        $this->applicationToken = $applicationToken;
+
+        return $this;
+    }
+
+    public function withApplicationStatusInstallation(ApplicationInstallationStatus $applicationInstallationStatus): self
+    {
+        $this->status = $applicationInstallationStatus;
+
+        return $this;
+    }
+
+    public function withApplicationStatus(ApplicationStatus $applicationStatus): self
+    {
+        $this->applicationStatus = $applicationStatus;
+
+        return $this;
+    }
+
+    public function withBitrix24AccountId(Uuid $uuid): self
+    {
+        $this->bitrix24AccountId = $uuid;
+
+        return $this;
+    }
+
+    public function withPortalLicenseFamily(PortalLicenseFamily $portalLicenseFamily): self
+    {
+        $this->portalLicenseFamily = $portalLicenseFamily;
+
+        return $this;
+    }
+
+    public function build(): ApplicationInstallation
+    {
+        $applicationInstallation = new ApplicationInstallation(
+            $this->id,
+            $this->bitrix24AccountId,
+            $this->applicationStatus,
+            $this->portalLicenseFamily,
+            $this->portalUsersCount,
+            $this->contactPersonId,
+            $this->bitrix24PartnerContactPersonId,
+            $this->bitrix24PartnerId,
+            $this->externalId,
+            $this->comment
+        );
+
+        if (!empty($this->status) && $this->status == ApplicationInstallationStatus::active) {
+            if ($this->applicationToken !== null && $this->applicationToken !== '') {
+                $applicationInstallation->applicationInstalled($this->applicationToken);
+            } else {
+                $applicationInstallation->applicationInstalled();
+            }
+        }
+
+        return $applicationInstallation;
+    }
+
+
+}
\ No newline at end of file
diff --git a/tests/Functional/ApplicationInstallations/Infrastructure/Doctrine/ApplicationInstallationRepositoryTest.php b/tests/Functional/ApplicationInstallations/Infrastructure/Doctrine/ApplicationInstallationRepositoryTest.php
new file mode 100644
index 0000000..925d0ac
--- /dev/null
+++ b/tests/Functional/ApplicationInstallations/Infrastructure/Doctrine/ApplicationInstallationRepositoryTest.php
@@ -0,0 +1,76 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Bitrix24\Lib\Tests\Functional\ApplicationInstallations\Infrastructure\Doctrine;
+
+use Bitrix24\Lib\ApplicationInstallations\Entity\ApplicationInstallation;
+use Bitrix24\Lib\ApplicationInstallations\Infrastructure\Doctrine\ApplicationInstallationRepository;
+use Bitrix24\SDK\Application\ApplicationStatus;
+use Bitrix24\SDK\Application\Contracts\ApplicationInstallations\Entity\ApplicationInstallationInterface;
+use Bitrix24\SDK\Application\Contracts\ApplicationInstallations\Entity\ApplicationInstallationStatus;
+use Bitrix24\SDK\Application\Contracts\ApplicationInstallations\Repository\ApplicationInstallationRepositoryInterface;
+use Bitrix24\SDK\Application\PortalLicenseFamily;
+use Bitrix24\SDK\Tests\Application\Contracts\ApplicationInstallations\Repository\ApplicationInstallationRepositoryInterfaceTest;
+use Bitrix24\SDK\Tests\Application\Contracts\TestRepositoryFlusherInterface;
+use Carbon\CarbonImmutable;
+use Symfony\Component\EventDispatcher\EventDispatcher;
+use Symfony\Component\Uid\Uuid;
+use PHPUnit\Framework\Attributes\CoversClass;
+use Bitrix24\Lib\Tests\EntityManagerFactory;
+use Bitrix24\Lib\Services\Flusher;
+use Bitrix24\Lib\Tests\Functional\FlusherDecorator;
+
+/**
+ * @internal
+ */
+#[CoversClass(ApplicationInstallationRepository::class)]
+class ApplicationInstallationRepositoryTest extends ApplicationInstallationRepositoryInterfaceTest
+{
+
+    #[\Override]
+    protected function createApplicationInstallationImplementation(
+        Uuid                          $uuid,
+        ApplicationInstallationStatus $applicationInstallationStatus,
+        Uuid                          $bitrix24AccountUuid,
+        ApplicationStatus             $applicationStatus,
+        PortalLicenseFamily           $portalLicenseFamily,
+        ?int                          $portalUsersCount,
+        ?Uuid                         $clientContactPersonUuid,
+        ?Uuid                         $partnerContactPersonUuid,
+        ?Uuid                         $partnerUuid,
+        ?string                       $externalId
+    ): ApplicationInstallationInterface
+    {
+        return new ApplicationInstallation(
+            $uuid,
+            $bitrix24AccountUuid,
+            $applicationStatus,
+            $portalLicenseFamily,
+            $portalUsersCount,
+            $clientContactPersonUuid,
+            $partnerContactPersonUuid,
+            $partnerUuid,
+            $externalId
+        );
+    }
+
+    #[\Override]
+    protected function createApplicationInstallationRepositoryImplementation(): ApplicationInstallationRepositoryInterface
+    {
+        $entityManager = EntityManagerFactory::get();
+
+        return new ApplicationInstallationRepository($entityManager);
+    }
+
+    #[\Override]
+    protected function createRepositoryFlusherImplementation(): TestRepositoryFlusherInterface
+    {
+        $entityManager = EntityManagerFactory::get();
+        $eventDispatcher = new EventDispatcher();
+
+        return new FlusherDecorator(new Flusher($entityManager, $eventDispatcher));
+    }
+
+}
+
diff --git a/tests/Functional/ApplicationInstallations/UseCase/Install/HandlerTest.php b/tests/Functional/ApplicationInstallations/UseCase/Install/HandlerTest.php
new file mode 100644
index 0000000..9da3891
--- /dev/null
+++ b/tests/Functional/ApplicationInstallations/UseCase/Install/HandlerTest.php
@@ -0,0 +1,349 @@
+<?php
+
+/**
+ * This file is part of the bitrix24-php-lib package.
+ *
+ * © Maksim Mesilov <mesilov.maxim@gmail.com>
+ *
+ * For the full copyright and license information, please view the MIT-LICENSE.txt
+ * file that was distributed with this source code.
+ */
+
+declare(strict_types=1);
+
+namespace Bitrix24\Lib\Tests\Functional\ApplicationInstallations\UseCase\Install;
+
+
+use Bitrix24\Lib\Bitrix24Accounts;
+
+use Bitrix24\Lib\Bitrix24Accounts\ValueObjects\Domain;
+use Bitrix24\Lib\Services\Flusher;
+use Bitrix24\Lib\ApplicationInstallations;
+use Bitrix24\Lib\Tests\EntityManagerFactory;
+
+use Bitrix24\Lib\Tests\Functional\ApplicationInstallations\Builders\ApplicationInstallationBuilder;
+use Bitrix24\Lib\Tests\Functional\Bitrix24Accounts\Builders\Bitrix24AccountBuilder;
+use Bitrix24\SDK\Application\ApplicationStatus;
+use Bitrix24\SDK\Application\Contracts\ApplicationInstallations\Entity\ApplicationInstallationInterface;
+use Bitrix24\SDK\Application\Contracts\ApplicationInstallations\Entity\ApplicationInstallationStatus;
+use Bitrix24\SDK\Application\Contracts\Bitrix24Accounts\Entity\Bitrix24AccountStatus;
+use Bitrix24\SDK\Application\Contracts\Events\AggregateRootEventsEmitterInterface;
+use Bitrix24\SDK\Application\PortalLicenseFamily;
+use Bitrix24\SDK\Core\Credentials\Scope;
+use Bitrix24\SDK\Core\Exceptions\InvalidArgumentException;
+
+use PHPUnit\Framework\Attributes\CoversClass;
+use PHPUnit\Framework\Attributes\Test;
+use PHPUnit\Framework\TestCase;
+use Psr\Log\NullLogger;
+
+use Symfony\Component\EventDispatcher\Debug\TraceableEventDispatcher;
+use Symfony\Component\EventDispatcher\EventDispatcher;
+use Symfony\Component\Stopwatch\Stopwatch;
+
+use Bitrix24\Lib\ApplicationInstallations\Infrastructure\Doctrine\ApplicationInstallationRepository;
+use Bitrix24\Lib\ApplicationInstallations\UseCase\Install\Handler;
+
+use Bitrix24\Lib\Bitrix24Accounts\Infrastructure\Doctrine\Bitrix24AccountRepository;
+use Symfony\Component\Uid\Uuid;
+
+/**
+ * @internal
+ */
+#[CoversClass(ApplicationInstallations\UseCase\Install\Handler::class)]
+class HandlerTest extends TestCase
+{
+    private Handler $handler;
+
+    private Flusher $flusher;
+
+    private ApplicationInstallationRepository $repository;
+
+    private Bitrix24AccountRepository $bitrix24accountRepository;
+
+    private TraceableEventDispatcher $eventDispatcher;
+
+    #[\Override]
+    protected function setUp(): void
+    {
+        $entityManager = EntityManagerFactory::get();
+        $this->eventDispatcher = new TraceableEventDispatcher(new EventDispatcher(), new Stopwatch());
+        $this->repository = new ApplicationInstallationRepository($entityManager);
+        $this->flusher = new Flusher($entityManager, $this->eventDispatcher);
+        $this->bitrix24accountRepository = new Bitrix24AccountRepository($entityManager);
+        $this->handler = new Handler(
+            $this->bitrix24accountRepository,
+            $this->repository,
+            $this->flusher,
+            new NullLogger()
+        );
+
+    }
+
+    /**
+     * @throws InvalidArgumentException
+     */
+    #[Test]
+    public function testNewInstallation(): void
+    {
+        $bitrix24AccountBuilder = (new Bitrix24AccountBuilder())
+            ->withApplicationScope(new Scope(['crm']))
+            ->build();
+
+
+        $applicationInstallationBuilder = (new ApplicationInstallationBuilder())
+            ->withApplicationStatus(new ApplicationStatus('F'))
+            ->withPortalLicenseFamily(PortalLicenseFamily::free)
+            ->build();
+
+
+        $this->handler->handle(
+            new ApplicationInstallations\UseCase\Install\Command(
+                $applicationInstallationBuilder->getApplicationStatus(),
+                $applicationInstallationBuilder->getPortalLicenseFamily(),
+                $applicationInstallationBuilder->getPortalUsersCount(),
+                $applicationInstallationBuilder->getContactPersonId(),
+                $applicationInstallationBuilder->getBitrix24PartnerContactPersonId(),
+                $applicationInstallationBuilder->getBitrix24PartnerId(),
+                $applicationInstallationBuilder->getExternalId(),
+                $applicationInstallationBuilder->getComment(),
+                $bitrix24AccountBuilder->getBitrix24UserId(),
+                $bitrix24AccountBuilder->isBitrix24UserAdmin(),
+                $bitrix24AccountBuilder->getMemberId(),
+                new Domain($bitrix24AccountBuilder->getDomainUrl()),
+                $bitrix24AccountBuilder->getAuthToken(),
+                $bitrix24AccountBuilder->getApplicationVersion(),
+                $bitrix24AccountBuilder->getApplicationScope()
+            )
+        );
+
+        $dispatchedEvents = $this->eventDispatcher->getOrphanedEvents();
+
+        $this->assertContains(\Bitrix24\SDK\Application\Contracts\Bitrix24Accounts\Events\Bitrix24AccountCreatedEvent::class, $dispatchedEvents);
+        $this->assertContains(\Bitrix24\SDK\Application\Contracts\ApplicationInstallations\Events\ApplicationInstallationCreatedEvent::class, $dispatchedEvents);
+        $this->assertContains(\Bitrix24\SDK\Application\Contracts\Bitrix24Accounts\Events\Bitrix24AccountApplicationInstalledEvent::class, $dispatchedEvents);
+        $this->assertContains(\Bitrix24\SDK\Application\Contracts\ApplicationInstallations\Events\ApplicationInstallationFinishedEvent::class, $dispatchedEvents);
+    }
+
+    /**
+     * @throws InvalidArgumentException
+     */
+    #[Test]
+    public function testNewInstallationWithToken(): void
+    {
+        $bitrix24AccountBuilder = (new Bitrix24AccountBuilder())
+            ->withApplicationScope(new Scope(['crm']))
+            ->build();
+
+
+        $applicationInstallationBuilder = (new ApplicationInstallationBuilder())
+            ->withApplicationStatus(new ApplicationStatus('F'))
+            ->withPortalLicenseFamily(PortalLicenseFamily::free)
+            ->build();
+
+        $newApplicationToken = Uuid::v7()->toRfc4122();
+
+        $this->handler->handle(
+            new ApplicationInstallations\UseCase\Install\Command(
+                $applicationInstallationBuilder->getApplicationStatus(),
+                $applicationInstallationBuilder->getPortalLicenseFamily(),
+                $applicationInstallationBuilder->getPortalUsersCount(),
+                $applicationInstallationBuilder->getContactPersonId(),
+                $applicationInstallationBuilder->getBitrix24PartnerContactPersonId(),
+                $applicationInstallationBuilder->getBitrix24PartnerId(),
+                $applicationInstallationBuilder->getExternalId(),
+                $applicationInstallationBuilder->getComment(),
+                $bitrix24AccountBuilder->getBitrix24UserId(),
+                $bitrix24AccountBuilder->isBitrix24UserAdmin(),
+                $bitrix24AccountBuilder->getMemberId(),
+                new Domain($bitrix24AccountBuilder->getDomainUrl()),
+                $bitrix24AccountBuilder->getAuthToken(),
+                $bitrix24AccountBuilder->getApplicationVersion(),
+                $bitrix24AccountBuilder->getApplicationScope(),
+                $newApplicationToken
+            )
+        );
+
+        $activeInstallation = $this->repository->findActiveByApplicationToken($newApplicationToken);
+        $this->assertNotNull($activeInstallation);
+
+        $dispatchedEvents = $this->eventDispatcher->getOrphanedEvents();
+
+        $this->assertContains(\Bitrix24\SDK\Application\Contracts\Bitrix24Accounts\Events\Bitrix24AccountCreatedEvent::class, $dispatchedEvents);
+        $this->assertContains(\Bitrix24\SDK\Application\Contracts\ApplicationInstallations\Events\ApplicationInstallationCreatedEvent::class, $dispatchedEvents);
+        $this->assertContains(\Bitrix24\SDK\Application\Contracts\Bitrix24Accounts\Events\Bitrix24AccountApplicationInstalledEvent::class, $dispatchedEvents);
+        $this->assertContains(\Bitrix24\SDK\Application\Contracts\ApplicationInstallations\Events\ApplicationInstallationFinishedEvent::class, $dispatchedEvents);
+    }
+
+    /**
+     * @throws InvalidArgumentException
+     */
+    #[Test]
+    public function testNewInstallationWithEmptyToken(): void
+    {
+        $bitrix24AccountBuilder = (new Bitrix24AccountBuilder())
+            ->withApplicationScope(new Scope(['crm']))
+            ->build();
+
+
+        $applicationInstallationBuilder = (new ApplicationInstallationBuilder())
+            ->withApplicationStatus(new ApplicationStatus('F'))
+            ->withPortalLicenseFamily(PortalLicenseFamily::free)
+            ->build();
+
+        $this->expectException(InvalidArgumentException::class);
+        $this->handler->handle(
+            new ApplicationInstallations\UseCase\Install\Command(
+                $applicationInstallationBuilder->getApplicationStatus(),
+                $applicationInstallationBuilder->getPortalLicenseFamily(),
+                $applicationInstallationBuilder->getPortalUsersCount(),
+                $applicationInstallationBuilder->getContactPersonId(),
+                $applicationInstallationBuilder->getBitrix24PartnerContactPersonId(),
+                $applicationInstallationBuilder->getBitrix24PartnerId(),
+                $applicationInstallationBuilder->getExternalId(),
+                $applicationInstallationBuilder->getComment(),
+                $bitrix24AccountBuilder->getBitrix24UserId(),
+                $bitrix24AccountBuilder->isBitrix24UserAdmin(),
+                $bitrix24AccountBuilder->getMemberId(),
+                new Domain($bitrix24AccountBuilder->getDomainUrl()),
+                $bitrix24AccountBuilder->getAuthToken(),
+                $bitrix24AccountBuilder->getApplicationVersion(),
+                $bitrix24AccountBuilder->getApplicationScope(),
+                ''
+            )
+        );
+    }
+
+    /**
+     * @throws InvalidArgumentException
+     */
+    #[Test]
+    public function testReinstallInstallation(): void
+    {
+
+        $memberId = Uuid::v4()->toRfc4122();
+
+        //Загружаем в базу данных аккаунт и установку приложения для тестирования переустановки.
+        $applicationToken = Uuid::v7()->toRfc4122();
+        $currentBitrix24Account = (new Bitrix24AccountBuilder())
+            ->withApplicationScope(new Scope(['crm']))
+            ->withStatus(Bitrix24AccountStatus::new)
+            ->withApplicationToken($applicationToken)
+            ->withMemberId($memberId)
+            ->withMaster(true)
+            ->build();
+
+
+        $applicationInstallation = (new ApplicationInstallationBuilder())
+            ->withApplicationStatus(new ApplicationStatus('F'))
+            ->withPortalLicenseFamily(PortalLicenseFamily::free)
+            ->withBitrix24AccountId($currentBitrix24Account->getId())
+            ->withApplicationStatusInstallation(ApplicationInstallationStatus::active)
+            ->build();
+
+        $this->bitrix24accountRepository->save($currentBitrix24Account);
+        $this->repository->save($applicationInstallation);
+        $this->flusher->flush();
+
+        $bitrix24AccountBuilder = (new Bitrix24AccountBuilder())
+            ->withApplicationScope(new Scope(['crm']))
+            ->withMemberId($memberId)
+            ->build();
+
+        $applicationInstallationBuilder = (new ApplicationInstallationBuilder())
+            ->withApplicationStatus(new ApplicationStatus('F'))
+            ->withPortalLicenseFamily(PortalLicenseFamily::free)
+            ->build();
+
+        $this->handler->handle(
+            new ApplicationInstallations\UseCase\Install\Command(
+                $applicationInstallationBuilder->getApplicationStatus(),
+                $applicationInstallationBuilder->getPortalLicenseFamily(),
+                $applicationInstallationBuilder->getPortalUsersCount(),
+                $applicationInstallationBuilder->getContactPersonId(),
+                $applicationInstallationBuilder->getBitrix24PartnerContactPersonId(),
+                $applicationInstallationBuilder->getBitrix24PartnerId(),
+                $applicationInstallationBuilder->getExternalId(),
+                $applicationInstallationBuilder->getComment(),
+                $bitrix24AccountBuilder->getBitrix24UserId(),
+                $bitrix24AccountBuilder->isBitrix24UserAdmin(),
+                $bitrix24AccountBuilder->getMemberId(),
+                new Domain($bitrix24AccountBuilder->getDomainUrl()),
+                $bitrix24AccountBuilder->getAuthToken(),
+                $bitrix24AccountBuilder->getApplicationVersion(),
+                $bitrix24AccountBuilder->getApplicationScope()
+            )
+        );
+
+        $dispatchedEvents = $this->eventDispatcher->getOrphanedEvents();
+
+        $this->assertContains(\Bitrix24\SDK\Application\Contracts\Bitrix24Accounts\Events\Bitrix24AccountCreatedEvent::class, $dispatchedEvents);
+        $this->assertContains(\Bitrix24\SDK\Application\Contracts\ApplicationInstallations\Events\ApplicationInstallationCreatedEvent::class, $dispatchedEvents);
+        $this->assertContains(\Bitrix24\SDK\Application\Contracts\Bitrix24Accounts\Events\Bitrix24AccountApplicationInstalledEvent::class, $dispatchedEvents);
+        $this->assertContains(\Bitrix24\SDK\Application\Contracts\ApplicationInstallations\Events\ApplicationInstallationFinishedEvent::class, $dispatchedEvents);
+    }
+
+    /**
+     * @throws InvalidArgumentException
+     */
+    #[Test]
+    public function testFewInstallationsOnOneAccount(): void
+    {
+
+        $memberId = Uuid::v4()->toRfc4122();
+
+        //Загружаем в базу данных аккаунт и установку приложения для тестирования переустановки.
+        $applicationToken = Uuid::v7()->toRfc4122();
+        $currentBitrix24Account = (new Bitrix24AccountBuilder())
+            ->withApplicationScope(new Scope(['crm']))
+            ->withStatus(Bitrix24AccountStatus::new)
+            ->withApplicationToken($applicationToken)
+            ->withMemberId($memberId)
+            ->build();
+
+
+        $applicationInstallation = (new ApplicationInstallationBuilder())
+            ->withApplicationStatus(new ApplicationStatus('F'))
+            ->withPortalLicenseFamily(PortalLicenseFamily::free)
+            ->withBitrix24AccountId($currentBitrix24Account->getId())
+            ->withApplicationStatusInstallation(ApplicationInstallationStatus::active)
+            ->build();
+
+        $this->bitrix24accountRepository->save($currentBitrix24Account);
+        $this->repository->save($applicationInstallation);
+        $this->flusher->flush();
+
+        $applicationInstallationBuilder = (new ApplicationInstallationBuilder())
+            ->withApplicationStatus(new ApplicationStatus('F'))
+            ->withPortalLicenseFamily(PortalLicenseFamily::free)
+            ->build();
+
+        $this->handler->handle(
+            new ApplicationInstallations\UseCase\Install\Command(
+                $applicationInstallationBuilder->getApplicationStatus(),
+                $applicationInstallationBuilder->getPortalLicenseFamily(),
+                $applicationInstallationBuilder->getPortalUsersCount(),
+                $applicationInstallationBuilder->getContactPersonId(),
+                $applicationInstallationBuilder->getBitrix24PartnerContactPersonId(),
+                $applicationInstallationBuilder->getBitrix24PartnerId(),
+                $applicationInstallationBuilder->getExternalId(),
+                $applicationInstallationBuilder->getComment(),
+                $currentBitrix24Account->getBitrix24UserId(),
+                $currentBitrix24Account->isBitrix24UserAdmin(),
+                $currentBitrix24Account->getMemberId(),
+                new Domain($currentBitrix24Account->getDomainUrl()),
+                $currentBitrix24Account->getAuthToken(),
+                $currentBitrix24Account->getApplicationVersion(),
+                $currentBitrix24Account->getApplicationScope()
+            )
+        );
+
+        $dispatchedEvents = $this->eventDispatcher->getOrphanedEvents();
+
+        $this->assertContains(\Bitrix24\SDK\Application\Contracts\Bitrix24Accounts\Events\Bitrix24AccountCreatedEvent::class, $dispatchedEvents);
+        $this->assertContains(\Bitrix24\SDK\Application\Contracts\ApplicationInstallations\Events\ApplicationInstallationCreatedEvent::class, $dispatchedEvents);
+        $this->assertContains(\Bitrix24\SDK\Application\Contracts\Bitrix24Accounts\Events\Bitrix24AccountApplicationInstalledEvent::class, $dispatchedEvents);
+        $this->assertContains(\Bitrix24\SDK\Application\Contracts\ApplicationInstallations\Events\ApplicationInstallationFinishedEvent::class, $dispatchedEvents);
+    }
+
+}
diff --git a/tests/Functional/ApplicationInstallations/UseCase/OnAppInstall/HandlerTest.php b/tests/Functional/ApplicationInstallations/UseCase/OnAppInstall/HandlerTest.php
new file mode 100644
index 0000000..ea179a5
--- /dev/null
+++ b/tests/Functional/ApplicationInstallations/UseCase/OnAppInstall/HandlerTest.php
@@ -0,0 +1,133 @@
+<?php
+
+/**
+ * This file is part of the bitrix24-php-lib package.
+ *
+ * © Maksim Mesilov <mesilov.maxim@gmail.com>
+ *
+ * For the full copyright and license information, please view the MIT-LICENSE.txt
+ * file that was distributed with this source code.
+ */
+
+declare(strict_types=1);
+
+namespace Bitrix24\Lib\Tests\Functional\ApplicationInstallations\UseCase\OnAppInstall;
+
+
+use Bitrix24\Lib\Bitrix24Accounts;
+
+use Bitrix24\Lib\Bitrix24Accounts\ValueObjects\Domain;
+use Bitrix24\Lib\Services\Flusher;
+use Bitrix24\Lib\ApplicationInstallations;
+use Bitrix24\Lib\Tests\EntityManagerFactory;
+
+use Bitrix24\Lib\Tests\Functional\ApplicationInstallations\Builders\ApplicationInstallationBuilder;
+use Bitrix24\Lib\Tests\Functional\Bitrix24Accounts\Builders\Bitrix24AccountBuilder;
+use Bitrix24\SDK\Application\ApplicationStatus;
+use Bitrix24\SDK\Application\Contracts\ApplicationInstallations\Entity\ApplicationInstallationStatus;
+use Bitrix24\SDK\Application\Contracts\Bitrix24Accounts\Entity\Bitrix24AccountStatus;
+use Bitrix24\SDK\Application\Contracts\Bitrix24Accounts\Exceptions\Bitrix24AccountNotFoundException;
+use Bitrix24\SDK\Application\PortalLicenseFamily;
+use Bitrix24\SDK\Core\Credentials\Scope;
+use Bitrix24\SDK\Core\Exceptions\InvalidArgumentException;
+
+use PHPUnit\Framework\Attributes\CoversClass;
+use PHPUnit\Framework\Attributes\Test;
+use PHPUnit\Framework\TestCase;
+use Psr\Log\NullLogger;
+
+use Symfony\Component\EventDispatcher\Debug\TraceableEventDispatcher;
+use Symfony\Component\EventDispatcher\EventDispatcher;
+use Symfony\Component\Stopwatch\Stopwatch;
+
+use Bitrix24\Lib\ApplicationInstallations\Infrastructure\Doctrine\ApplicationInstallationRepository;
+use Bitrix24\Lib\ApplicationInstallations\UseCase\OnAppInstall\Handler;
+
+use Bitrix24\Lib\Bitrix24Accounts\Infrastructure\Doctrine\Bitrix24AccountRepository;
+use Symfony\Component\Uid\Uuid;
+
+/**
+ * @internal
+ */
+#[CoversClass(ApplicationInstallations\UseCase\OnAppInstall\Handler::class)]
+class HandlerTest extends TestCase
+{
+    private Handler $handler;
+
+    private Flusher $flusher;
+
+    private ApplicationInstallationRepository $applicationInstallationRepository;
+
+    private Bitrix24AccountRepository $bitrix24accountRepository;
+
+    private TraceableEventDispatcher $eventDispatcher;
+
+    #[\Override]
+    protected function setUp(): void
+    {
+        $entityManager = EntityManagerFactory::get();
+        $this->eventDispatcher = new TraceableEventDispatcher(new EventDispatcher(), new Stopwatch());
+        $this->applicationInstallationRepository = new ApplicationInstallationRepository($entityManager);
+        $this->flusher = new Flusher($entityManager, $this->eventDispatcher);
+        $this->bitrix24accountRepository = new Bitrix24AccountRepository($entityManager);
+        $this->handler = new Handler(
+            $this->bitrix24accountRepository,
+            $this->applicationInstallationRepository,
+            $this->flusher,
+            new NullLogger()
+        );
+
+    }
+
+    /**
+     * @throws InvalidArgumentException|Bitrix24AccountNotFoundException
+     */
+    #[Test]
+    public function testEventOnAppInstall(): void
+    {
+        $memberId = Uuid::v4()->toRfc4122();
+        $domainUrl = Uuid::v4()->toRfc4122().'-example.com';
+        $applicationToken = Uuid::v7()->toRfc4122();
+        $applicationStatus = 'T';
+
+        $bitrix24Account = (new Bitrix24AccountBuilder())
+            ->withApplicationScope(new Scope(['crm']))
+            ->withStatus(Bitrix24AccountStatus::new)
+            ->withMemberId($memberId)
+            ->withDomainUrl($domainUrl)
+            ->withInstalled()
+            ->withMaster(true)
+            ->build();
+
+        $applicationInstallationBuilder = (new ApplicationInstallationBuilder())
+            ->withApplicationStatus(new ApplicationStatus('F'))
+            ->withPortalLicenseFamily(PortalLicenseFamily::free)
+            ->withBitrix24AccountId($bitrix24Account->getId())
+            ->withApplicationStatusInstallation(ApplicationInstallationStatus::active)
+            ->build();
+
+        $this->bitrix24accountRepository->save($bitrix24Account);
+        $this->applicationInstallationRepository->save($applicationInstallationBuilder);
+        $this->flusher->flush();
+
+        $this->handler->handle(
+            new ApplicationInstallations\UseCase\OnAppInstall\Command(
+                $memberId,
+                new Domain($domainUrl),
+                $applicationToken,
+                $applicationStatus
+            )
+        );
+
+        $updated = $this->bitrix24accountRepository->getById($bitrix24Account->getId());
+
+        $this->assertTrue(
+            $updated->isApplicationTokenValid($applicationToken),
+            sprintf(
+                'failed application token «%s» validation for bitrix24 account with id «%s»',
+                $applicationToken,
+                $bitrix24Account->getId()->toString()
+            )
+        );
+    }
+}
diff --git a/tests/Functional/ApplicationInstallations/UseCase/Uninstall/HandlerTest.php b/tests/Functional/ApplicationInstallations/UseCase/Uninstall/HandlerTest.php
new file mode 100644
index 0000000..8cbad0a
--- /dev/null
+++ b/tests/Functional/ApplicationInstallations/UseCase/Uninstall/HandlerTest.php
@@ -0,0 +1,241 @@
+<?php
+
+/**
+ * This file is part of the bitrix24-php-lib package.
+ *
+ * © Maksim Mesilov <mesilov.maxim@gmail.com>
+ *
+ * For the full copyright and license information, please view the MIT-LICENSE.txt
+ * file that was distributed with this source code.
+ */
+
+declare(strict_types=1);
+
+namespace Bitrix24\Lib\Tests\Functional\ApplicationInstallations\UseCase\Uninstall;
+
+
+use Bitrix24\Lib\Bitrix24Accounts;
+
+use Bitrix24\Lib\Bitrix24Accounts\ValueObjects\Domain;
+use Bitrix24\Lib\Services\Flusher;
+use Bitrix24\Lib\ApplicationInstallations;
+use Bitrix24\Lib\Tests\EntityManagerFactory;
+
+use Bitrix24\Lib\Tests\Functional\ApplicationInstallations\Builders\ApplicationInstallationBuilder;
+use Bitrix24\Lib\Tests\Functional\Bitrix24Accounts\Builders\Bitrix24AccountBuilder;
+use Bitrix24\SDK\Application\ApplicationStatus;
+use Bitrix24\SDK\Application\Contracts\ApplicationInstallations\Entity\ApplicationInstallationStatus;
+use Bitrix24\SDK\Application\Contracts\ApplicationInstallations\Exceptions\ApplicationInstallationNotFoundException;
+use Bitrix24\SDK\Application\Contracts\Bitrix24Accounts\Entity\Bitrix24AccountStatus;
+use Bitrix24\SDK\Application\PortalLicenseFamily;
+use Bitrix24\SDK\Core\Credentials\Scope;
+use Bitrix24\SDK\Core\Exceptions\InvalidArgumentException;
+
+use PHPUnit\Framework\Attributes\CoversClass;
+use PHPUnit\Framework\Attributes\Test;
+use PHPUnit\Framework\TestCase;
+use Psr\Log\NullLogger;
+
+use Symfony\Component\EventDispatcher\Debug\TraceableEventDispatcher;
+use Symfony\Component\EventDispatcher\EventDispatcher;
+use Symfony\Component\Stopwatch\Stopwatch;
+
+use Bitrix24\Lib\ApplicationInstallations\Infrastructure\Doctrine\ApplicationInstallationRepository;
+use Bitrix24\Lib\ApplicationInstallations\UseCase\Uninstall\Handler;
+
+use Bitrix24\Lib\Bitrix24Accounts\Infrastructure\Doctrine\Bitrix24AccountRepository;
+use Symfony\Component\Uid\Uuid;
+
+
+/**
+ * @internal
+ */
+#[CoversClass(ApplicationInstallations\UseCase\Uninstall\Handler::class)]
+class HandlerTest extends TestCase
+{
+    private Handler $handler;
+
+    private Flusher $flusher;
+
+    private ApplicationInstallationRepository $repository;
+
+    private Bitrix24AccountRepository $bitrix24accountRepository;
+
+    private TraceableEventDispatcher $eventDispatcher;
+
+    #[\Override]
+    protected function setUp(): void
+    {
+        $entityManager = EntityManagerFactory::get();
+        $this->eventDispatcher = new TraceableEventDispatcher(new EventDispatcher(), new Stopwatch());
+        $this->repository = new ApplicationInstallationRepository($entityManager);
+        $this->flusher = new Flusher($entityManager, $this->eventDispatcher);
+        $this->bitrix24accountRepository = new Bitrix24AccountRepository($entityManager);
+        $this->handler = new Handler(
+            $this->bitrix24accountRepository,
+            $this->repository,
+            $this->flusher,
+            new NullLogger()
+        );
+    }
+
+    /**
+     * @throws InvalidArgumentException
+     */
+    #[Test]
+    public function testUninstall(): void
+    {
+        //Загружаем в базу данных аккаунт и установку приложения для их деинсталяции.
+        $applicationToken = Uuid::v7()->toRfc4122();
+        $oldBitrix24Account = (new Bitrix24AccountBuilder())
+            ->withApplicationScope(new Scope(['crm']))
+            ->withStatus(Bitrix24AccountStatus::new)
+            ->withApplicationToken($applicationToken)
+            ->withMaster(true)
+            ->withSetToken()
+            ->withInstalled()
+            ->build();
+
+        $this->bitrix24accountRepository->save($oldBitrix24Account);
+
+        $oldApplicationInstallation = (new ApplicationInstallationBuilder())
+            ->withApplicationStatus(new ApplicationStatus('F'))
+            ->withPortalLicenseFamily(PortalLicenseFamily::free)
+            ->withBitrix24AccountId($oldBitrix24Account->getId())
+            ->withApplicationStatusInstallation(ApplicationInstallationStatus::active)
+            ->withApplicationToken($applicationToken)
+            ->build();
+
+        $this->repository->save($oldApplicationInstallation);
+
+        $this->flusher->flush();
+
+        $this->handler->handle(
+            new ApplicationInstallations\UseCase\Uninstall\Command(
+                new Domain($oldBitrix24Account->getDomainUrl()),
+                $oldBitrix24Account->getMemberId(),
+                $applicationToken
+            )
+        );
+
+        $dispatchedEvents = $this->eventDispatcher->getOrphanedEvents();
+        $this->assertContains(\Bitrix24\SDK\Application\Contracts\Bitrix24Accounts\Events\Bitrix24AccountApplicationUninstalledEvent::class, $dispatchedEvents);
+
+        $this->expectException(ApplicationInstallationNotFoundException::class);
+        $this->repository->getById($oldApplicationInstallation->getId());
+    }
+
+    /**
+     * @throws InvalidArgumentException
+     */
+    #[Test]
+    public function testUninstallWithNotValidToken(): void
+    {
+        $applicationToken = Uuid::v7()->toRfc4122();
+        $oldBitrix24Account = (new Bitrix24AccountBuilder())
+            ->withApplicationScope(new Scope(['crm']))
+            ->withStatus(Bitrix24AccountStatus::new)
+            ->withApplicationToken($applicationToken)
+            ->withMaster(true)
+            ->withSetToken()
+            ->withInstalled()
+            ->build();
+
+        $this->bitrix24accountRepository->save($oldBitrix24Account);
+
+        $oldApplicationInstallation = (new ApplicationInstallationBuilder())
+            ->withApplicationStatus(new ApplicationStatus('F'))
+            ->withPortalLicenseFamily(PortalLicenseFamily::free)
+            ->withBitrix24AccountId($oldBitrix24Account->getId())
+            ->withApplicationStatusInstallation(ApplicationInstallationStatus::active)
+            ->withApplicationToken($applicationToken)
+            ->build();
+
+        $this->repository->save($oldApplicationInstallation);
+
+        $this->flusher->flush();
+
+        $this->handler->handle(
+            new ApplicationInstallations\UseCase\Uninstall\Command(
+                new Domain($oldBitrix24Account->getDomainUrl()),
+                $oldBitrix24Account->getMemberId(),
+                'testNotValidToken'
+            )
+        );
+
+        $applicationInstallation = $this->repository->getById($oldApplicationInstallation->getId());
+
+        $this->assertEquals(ApplicationInstallationStatus::active, $applicationInstallation->getStatus());
+        $this->assertEquals($oldApplicationInstallation->getUpdatedAt(), $applicationInstallation->getUpdatedAt());
+
+        $bitrix24Account = $this->bitrix24accountRepository->getById($oldBitrix24Account->getId());
+
+        $this->assertEquals(Bitrix24AccountStatus::active, $bitrix24Account->getStatus());
+        $this->assertEquals($oldBitrix24Account->getUpdatedAt(), $bitrix24Account->getUpdatedAt());
+    }
+
+    public function testUninstallWithFewAccount(): void
+    {
+        $memberId = Uuid::v4()->toRfc4122();
+        //Загружаем в базу данных аккаунт и установку приложения для их деинсталяции.
+        $applicationToken = Uuid::v7()->toRfc4122();
+        $oldBitrix24Account = (new Bitrix24AccountBuilder())
+            ->withApplicationScope(new Scope(['crm']))
+            ->withStatus(Bitrix24AccountStatus::new)
+            ->withApplicationToken($applicationToken)
+            ->withMaster(true)
+            ->withMemberId($memberId)
+            ->withSetToken()
+            ->build();
+
+        $this->bitrix24accountRepository->save($oldBitrix24Account);
+
+        $bitrix24Account = (new Bitrix24AccountBuilder())
+            ->withApplicationScope(new Scope(['crm']))
+            ->withStatus(Bitrix24AccountStatus::new)
+            ->withMemberId($memberId)
+            ->build();
+
+        $this->bitrix24accountRepository->save($bitrix24Account);
+
+        $oldApplicationInstallation = (new ApplicationInstallationBuilder())
+            ->withApplicationStatus(new ApplicationStatus('F'))
+            ->withPortalLicenseFamily(PortalLicenseFamily::free)
+            ->withBitrix24AccountId($oldBitrix24Account->getId())
+            ->withApplicationStatusInstallation(ApplicationInstallationStatus::active)
+            ->withApplicationToken($applicationToken)
+            ->build();
+
+        $this->repository->save($oldApplicationInstallation);
+
+        $this->flusher->flush();
+
+        $this->handler->handle(
+            new ApplicationInstallations\UseCase\Uninstall\Command(
+                new Domain($oldBitrix24Account->getDomainUrl()),
+                $oldBitrix24Account->getMemberId(),
+                $applicationToken
+            )
+        );
+
+        $dispatchedEvents = $this->eventDispatcher->getOrphanedEvents();
+
+        $this->assertContains(\Bitrix24\SDK\Application\Contracts\Bitrix24Accounts\Events\Bitrix24AccountApplicationUninstalledEvent::class, $dispatchedEvents);
+
+        $applicationInstallation = $this->repository->find($oldApplicationInstallation->getId());
+
+        $this->assertEquals(ApplicationInstallationStatus::deleted, $applicationInstallation->getStatus());
+
+        $bitrix24Accounts = $this->bitrix24accountRepository->findByMemberId($memberId);
+
+        foreach ($bitrix24Accounts as $bitrix24Account) {
+            $this->assertSame(
+                Bitrix24AccountStatus::deleted,
+                $bitrix24Account->getStatus(),
+                sprintf('Account %s не в статусе "удалён"', $bitrix24Account->getId())
+            );
+        }
+    }
+
+
+}
\ No newline at end of file
diff --git a/tests/Functional/Bitrix24Accounts/Builders/Bitrix24AccountBuilder.php b/tests/Functional/Bitrix24Accounts/Builders/Bitrix24AccountBuilder.php
index bff547e..77b6bed 100644
--- a/tests/Functional/Bitrix24Accounts/Builders/Bitrix24AccountBuilder.php
+++ b/tests/Functional/Bitrix24Accounts/Builders/Bitrix24AccountBuilder.php
@@ -14,9 +14,7 @@
 namespace Bitrix24\Lib\Tests\Functional\Bitrix24Accounts\Builders;
 
 use Bitrix24\Lib\Bitrix24Accounts\Entity\Bitrix24Account;
-use Bitrix24\SDK\Application\Contracts\Bitrix24Accounts\Entity\Bitrix24AccountInterface;
 use Bitrix24\SDK\Application\Contracts\Bitrix24Accounts\Entity\Bitrix24AccountStatus;
-use Bitrix24\SDK\Application\Contracts\Events\AggregateRootEventsEmitterInterface;
 use Bitrix24\SDK\Core\Credentials\AuthToken;
 use Bitrix24\SDK\Core\Credentials\Scope;
 use Carbon\CarbonImmutable;
@@ -35,20 +33,22 @@ class Bitrix24AccountBuilder
 
     private string $domainUrl;
 
-    private Bitrix24AccountStatus $status = Bitrix24AccountStatus::active;
+    private Bitrix24AccountStatus $status;
 
     private readonly AuthToken $authToken;
 
-    private readonly CarbonImmutable $createdAt;
-
-    private readonly CarbonImmutable $updatedAt;
-
     private readonly int $applicationVersion;
 
     private Scope $applicationScope;
 
     private ?string $applicationToken = null;
 
+    private bool $isMasterAccount = false;
+
+    private bool $isSetToken = false;
+
+    private bool $isInstalled = false;
+
     public function __construct()
     {
         $this->id = Uuid::v7();
@@ -57,8 +57,6 @@ public function __construct()
         $this->memberId = Uuid::v4()->toRfc4122();
         $this->domainUrl = Uuid::v4()->toRfc4122().'-example.com';
         $this->authToken = new AuthToken('old_1', 'old_2', 3600);
-        $this->createdAt = CarbonImmutable::now();
-        $this->updatedAt = CarbonImmutable::now();
         $this->applicationVersion = 1;
         $this->applicationScope = new Scope();
     }
@@ -98,6 +96,27 @@ public function withStatus(Bitrix24AccountStatus $bitrix24AccountStatus): self
         return $this;
     }
 
+    public function withSetToken(): self
+    {
+        $this->isSetToken = true;
+
+        return $this;
+    }
+
+    public function withMaster(bool $isMaster): self
+    {
+        $this->isMasterAccount = $isMaster;
+
+        return $this;
+    }
+
+    public function withInstalled(): self
+    {
+        $this->isInstalled = true;
+
+        return $this;
+    }
+
     public function build(): Bitrix24Account
     {
         $bitrix24Account = new Bitrix24Account(
@@ -106,18 +125,22 @@ public function build(): Bitrix24Account
             $this->isBitrix24UserAdmin,
             $this->memberId,
             $this->domainUrl,
-            $this->status,
             $this->authToken,
-            $this->createdAt,
-            $this->updatedAt,
             $this->applicationVersion,
-            $this->applicationScope
+            $this->applicationScope,
+            $this->isMasterAccount
         );
 
-        if ($this->applicationToken !== null && Bitrix24AccountStatus::new == $this->status) {
-            $bitrix24Account->applicationInstalled($this->applicationToken);
+        if ($this->isInstalled && Bitrix24AccountStatus::new == $this->status) {
+            $bitrix24Account->applicationInstalled(null);
+        }
+
+        if ($this->isSetToken && $this->applicationToken !== null) {
+            $bitrix24Account->setApplicationToken($this->applicationToken);
         }
 
+
+
         return $bitrix24Account;
     }
 }
diff --git a/tests/Functional/Bitrix24Accounts/Infrastructure/Doctrine/Bitrix24AccountRepositoryTest.php b/tests/Functional/Bitrix24Accounts/Infrastructure/Doctrine/Bitrix24AccountRepositoryTest.php
index 4736e55..6d4c1ac 100644
--- a/tests/Functional/Bitrix24Accounts/Infrastructure/Doctrine/Bitrix24AccountRepositoryTest.php
+++ b/tests/Functional/Bitrix24Accounts/Infrastructure/Doctrine/Bitrix24AccountRepositoryTest.php
@@ -41,12 +41,10 @@ protected function createBitrix24AccountImplementation(
         Uuid $uuid,
         int $bitrix24UserId,
         bool $isBitrix24UserAdmin,
+        bool $isMasterAccount,
         string $memberId,
         string $domainUrl,
-        Bitrix24AccountStatus $bitrix24AccountStatus,
         AuthToken $authToken,
-        CarbonImmutable $createdAt,
-        CarbonImmutable $updatedAt,
         int $applicationVersion,
         Scope $applicationScope
     ): Bitrix24AccountInterface {
@@ -56,12 +54,10 @@ protected function createBitrix24AccountImplementation(
             $isBitrix24UserAdmin,
             $memberId,
             $domainUrl,
-            $bitrix24AccountStatus,
             $authToken,
-            $createdAt,
-            $updatedAt,
             $applicationVersion,
-            $applicationScope
+            $applicationScope,
+            $isMasterAccount
         );
     }
 
diff --git a/tests/Functional/Bitrix24Accounts/UseCase/InstallFinish/HandlerTest.php b/tests/Functional/Bitrix24Accounts/UseCase/InstallFinish/HandlerTest.php
index f0d1ac0..5d84d7e 100644
--- a/tests/Functional/Bitrix24Accounts/UseCase/InstallFinish/HandlerTest.php
+++ b/tests/Functional/Bitrix24Accounts/UseCase/InstallFinish/HandlerTest.php
@@ -86,14 +86,6 @@ public function testFinishInstallationApplication(): void
 
         $updated = $this->repository->getById($bitrix24Account->getId());
         $this->assertEquals(Bitrix24AccountStatus::active, $updated->getStatus(), 'expected status is active');
-        $this->assertTrue(
-            $updated->isApplicationTokenValid($applicationToken),
-            sprintf(
-                'failed application token «%s» validation for bitrix24 account with id «%s»',
-                $applicationToken,
-                $bitrix24Account->getId()->toString()
-            )
-        );
         $this->assertTrue(
             in_array(Bitrix24AccountApplicationInstalledEvent::class, $this->eventDispatcher->getOrphanedEvents(), true),
             sprintf(
diff --git a/tests/Functional/Bitrix24Accounts/UseCase/RenewAuthToken/HandlerTest.php b/tests/Functional/Bitrix24Accounts/UseCase/RenewAuthToken/HandlerTest.php
index 31a5855..479f2cb 100644
--- a/tests/Functional/Bitrix24Accounts/UseCase/RenewAuthToken/HandlerTest.php
+++ b/tests/Functional/Bitrix24Accounts/UseCase/RenewAuthToken/HandlerTest.php
@@ -20,6 +20,7 @@
 use Bitrix24\Lib\Tests\EntityManagerFactory;
 use Bitrix24\Lib\Tests\Functional\Bitrix24Accounts\Builders\Bitrix24AccountBuilder;
 use Bitrix24\SDK\Application\ApplicationStatus;
+use Bitrix24\SDK\Application\Contracts\Bitrix24Accounts\Entity\Bitrix24AccountStatus;
 use Bitrix24\SDK\Application\Contracts\Bitrix24Accounts\Repository\Bitrix24AccountRepositoryInterface;
 use Bitrix24\SDK\Core\Credentials\AuthToken;
 use Bitrix24\SDK\Core\Response\DTO\RenewedAuthToken;
@@ -30,6 +31,7 @@
 use Symfony\Component\EventDispatcher\Debug\TraceableEventDispatcher;
 use Symfony\Component\EventDispatcher\EventDispatcher;
 use Symfony\Component\Stopwatch\Stopwatch;
+use Symfony\Component\Uid\Uuid;
 
 /**
  * @internal
@@ -64,7 +66,11 @@ protected function setUp(): void
     #[Test]
     public function testRenewAuthTokenWithoutBitrix24UserId(): void
     {
+        $applicationToken = Uuid::v7()->toRfc4122();
         $bitrix24Account = (new Bitrix24AccountBuilder())
+            ->withStatus(Bitrix24AccountStatus::new)
+            ->withApplicationToken($applicationToken)
+            ->withInstalled()
             ->build();
         $this->repository->save($bitrix24Account);
         $this->flusher->flush();
diff --git a/tests/Functional/Bitrix24Accounts/UseCase/Uninstall/HandlerTest.php b/tests/Functional/Bitrix24Accounts/UseCase/Uninstall/HandlerTest.php
index a902791..d761e60 100644
--- a/tests/Functional/Bitrix24Accounts/UseCase/Uninstall/HandlerTest.php
+++ b/tests/Functional/Bitrix24Accounts/UseCase/Uninstall/HandlerTest.php
@@ -75,11 +75,12 @@ public function testUninstallApplication(): void
         $bitrix24Account = (new Bitrix24AccountBuilder())
             ->withStatus(Bitrix24AccountStatus::new)
             ->withApplicationToken($applicationToken)
+            ->withInstalled()
+            ->withSetToken()
             ->build();
 
         $this->repository->save($bitrix24Account);
         $this->flusher->flush();
-
         $this->handler->handle(new Bitrix24Accounts\UseCase\Uninstall\Command($applicationToken));
 
         $this->expectException(Bitrix24AccountNotFoundException::class);
diff --git a/tests/Functional/Bitrix24Accounts/UseCase/UpdateVersion/HandlerTest.php b/tests/Functional/Bitrix24Accounts/UseCase/UpdateVersion/HandlerTest.php
index 8147815..12412d7 100644
--- a/tests/Functional/Bitrix24Accounts/UseCase/UpdateVersion/HandlerTest.php
+++ b/tests/Functional/Bitrix24Accounts/UseCase/UpdateVersion/HandlerTest.php
@@ -69,8 +69,9 @@ public function testSuccessUpdateVersion(): void
         $applicationToken = Uuid::v7()->toRfc4122();
 
         $bitrix24Account = (new Bitrix24AccountBuilder())
-            ->withStatus(Bitrix24AccountStatus::active)
+            ->withStatus(Bitrix24AccountStatus::new)
             ->withApplicationToken($applicationToken)
+            ->withInstalled()
             ->build();
 
         $this->repository->save($bitrix24Account);
@@ -98,7 +99,7 @@ public function testNotFoundBitrix24AccountForUpdateVersion(): void
         $applicationToken = Uuid::v7()->toRfc4122();
 
         $bitrix24Account = (new Bitrix24AccountBuilder())
-            ->withStatus(Bitrix24AccountStatus::active)
+            ->withStatus(Bitrix24AccountStatus::new)
             ->withApplicationToken($applicationToken)
             ->build();
 
@@ -126,8 +127,11 @@ public function testNotFoundBitrix24AccountForUpdateVersion(): void
     #[Test]
     public function testNotValidVersionForUpdateVersion(): void
     {
+        $applicationToken = Uuid::v7()->toRfc4122();
         $bitrix24Account = (new Bitrix24AccountBuilder())
-            ->withStatus(Bitrix24AccountStatus::active)
+            ->withStatus(Bitrix24AccountStatus::new)
+            ->withApplicationToken($applicationToken)
+            ->withInstalled()
             ->build();
 
 
diff --git a/tests/Unit/ApplicationInstallations/Entity/ApplicationInstallationTest.php b/tests/Unit/ApplicationInstallations/Entity/ApplicationInstallationTest.php
new file mode 100644
index 0000000..98a4f27
--- /dev/null
+++ b/tests/Unit/ApplicationInstallations/Entity/ApplicationInstallationTest.php
@@ -0,0 +1,49 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Bitrix24\Lib\Tests\Unit\ApplicationInstallations\Entity;
+
+use Bitrix24\Lib\ApplicationInstallations\Entity\ApplicationInstallation;
+use Bitrix24\SDK\Application\ApplicationStatus;
+use Bitrix24\SDK\Application\Contracts\ApplicationInstallations\Entity\ApplicationInstallationInterface;
+use Bitrix24\SDK\Application\Contracts\ApplicationInstallations\Entity\ApplicationInstallationStatus;
+use Bitrix24\SDK\Application\PortalLicenseFamily;
+use Bitrix24\SDK\Tests\Application\Contracts\ApplicationInstallations\Entity\ApplicationInstallationInterfaceTest;
+use Carbon\CarbonImmutable;
+use PHPUnit\Framework\Attributes\CoversClass;
+use Symfony\Component\Uid\Uuid;
+
+/**
+ * @internal
+ */
+#[CoversClass(ApplicationInstallation::class)]
+class ApplicationInstallationTest extends ApplicationInstallationInterfaceTest
+{
+    #[\Override]
+    protected function createApplicationInstallationImplementation(
+        Uuid $uuid,
+        ApplicationInstallationStatus $applicationInstallationStatus,
+        Uuid $bitrix24AccountUuid,
+        ApplicationStatus $applicationStatus,
+        PortalLicenseFamily $portalLicenseFamily,
+        ?int $portalUsersCount,
+        ?Uuid $clientContactPersonUuid,
+        ?Uuid $partnerContactPersonUuid,
+        ?Uuid $partnerUuid,
+        ?string $externalId):
+    ApplicationInstallationInterface {
+        return new ApplicationInstallation(
+            $uuid,
+            $bitrix24AccountUuid,
+            $applicationStatus,
+            $portalLicenseFamily,
+            $portalUsersCount,
+            $clientContactPersonUuid,
+            $partnerContactPersonUuid,
+            $partnerUuid,
+            $externalId,
+            null
+        );
+    }
+}
diff --git a/tests/Unit/ApplicationInstallations/MethodValidation/ChangePortalLicenseFamily.php b/tests/Unit/ApplicationInstallations/MethodValidation/ChangePortalLicenseFamily.php
new file mode 100644
index 0000000..1e94ace
--- /dev/null
+++ b/tests/Unit/ApplicationInstallations/MethodValidation/ChangePortalLicenseFamily.php
@@ -0,0 +1,33 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Bitrix24\Lib\Tests\Unit\ApplicationInstallations\MethodValidation;
+
+use Bitrix24\SDK\Application\ApplicationStatus;
+use Bitrix24\SDK\Application\PortalLicenseFamily;
+use PHPUnit\Framework\TestCase;
+use Bitrix24\Lib\Tests\Functional\ApplicationInstallations\Builders\ApplicationInstallationBuilder;
+class ChangePortalLicenseFamily extends TestCase
+{
+   public function testEqualsChangePortalLicenseFamily(): void
+   {
+       $applicationInstallation = (new ApplicationInstallationBuilder)
+           ->withPortalLicenseFamily(PortalLicenseFamily::free)
+           ->withApplicationStatus(new ApplicationStatus('F'))
+           ->build();
+       $applicationInstallation->changePortalLicenseFamily(PortalLicenseFamily::basic);
+       $this->assertEquals(PortalLicenseFamily::basic, $applicationInstallation->getPortalLicenseFamily());
+   }
+
+    public function testNotEqualsChangePortalLicenseFamily(): void
+    {
+        $applicationInstallation = (new ApplicationInstallationBuilder)
+            ->withPortalLicenseFamily(PortalLicenseFamily::free)
+            ->withApplicationStatus(new ApplicationStatus('F'))
+            ->build();
+        $initialUpdatedAt = $applicationInstallation->getUpdatedAt();
+        $applicationInstallation->changePortalLicenseFamily(PortalLicenseFamily::free);
+        $this->assertEquals($initialUpdatedAt, $applicationInstallation->getUpdatedAt());
+    }
+}
diff --git a/tests/Unit/ApplicationInstallations/UseCase/Install/CommandTest.php b/tests/Unit/ApplicationInstallations/UseCase/Install/CommandTest.php
new file mode 100644
index 0000000..aae26c7
--- /dev/null
+++ b/tests/Unit/ApplicationInstallations/UseCase/Install/CommandTest.php
@@ -0,0 +1,256 @@
+<?php
+
+
+declare(strict_types=1);
+
+namespace Bitrix24\Lib\Tests\Unit\ApplicationInstallations\UseCase\Install;
+
+use Bitrix24\Lib\Bitrix24Accounts\ValueObjects\Domain;
+use Bitrix24\Lib\Tests\Functional\Bitrix24Accounts\Builders\Bitrix24AccountBuilder;
+use Bitrix24\SDK\Application\ApplicationStatus;
+use Bitrix24\SDK\Application\PortalLicenseFamily;
+use Bitrix24\SDK\Core\Credentials\AuthToken;
+use Bitrix24\SDK\Core\Credentials\Scope;
+use Bitrix24\SDK\Core\Exceptions\InvalidArgumentException;
+use PHPUnit\Framework\Attributes\CoversClass;
+use PHPUnit\Framework\TestCase;
+use PHPUnit\Framework\Attributes\DataProvider;
+use PHPUnit\Framework\Attributes\Test;
+use Bitrix24\Lib\ApplicationInstallations\UseCase\Install\Command;
+use Symfony\Component\Uid\Uuid;
+use Bitrix24\Lib\Tests\Functional\ApplicationInstallations\Builders\ApplicationInstallationBuilder;
+
+/**
+ * @internal
+ */
+#[CoversClass(Command::class)]
+class CommandTest extends TestCase
+{
+    #[Test]
+    #[DataProvider('dataForCommand')]
+    public function testValidCommand(
+        ApplicationStatus   $applicationStatus,
+        PortalLicenseFamily $portalLicenseFamily,
+        ?int                $portalUsersCount,
+        ?Uuid               $contactPersonId,
+        ?Uuid               $bitrix24PartnerContactPersonId,
+        ?Uuid               $bitrix24PartnerId,
+        ?string             $externalId,
+        ?string             $comment,
+        int                 $bitrix24UserId,
+        bool                $isBitrix24UserAdmin,
+        string              $memberId,
+        Domain              $domain,
+        AuthToken           $authToken,
+        int                 $applicationVersion,
+        Scope               $applicationScope,
+        ?string             $applicationToken,
+        ?string             $expectedException,
+
+    ): void
+    {
+        if (null !== $expectedException) {
+            $this->expectException($expectedException);
+        }
+
+        $command = new Command(
+            $applicationStatus,
+            $portalLicenseFamily,
+            $portalUsersCount,
+            $contactPersonId,
+            $bitrix24PartnerContactPersonId,
+            $bitrix24PartnerId,
+            $externalId,
+            $comment,
+            $bitrix24UserId,
+            $isBitrix24UserAdmin,
+            $memberId,
+            $domain,
+            $authToken,
+            $applicationVersion,
+            $applicationScope,
+            $applicationToken,
+        );
+
+        if (null === $expectedException) {
+            // Проверяем, что объект создан и является экземпляром нужного класса
+            $this->assertInstanceOf(Command::class, $command);
+        }
+    }
+
+    public static function dataForCommand(): \Generator
+    {
+        $applicationInstallationBuilder = (new ApplicationInstallationBuilder())
+            ->withApplicationStatus(new ApplicationStatus('F'))
+            ->withPortalLicenseFamily(PortalLicenseFamily::free)
+            ->build();
+
+        $bitrix24AccountBuilder = (new Bitrix24AccountBuilder())
+            ->withApplicationScope(new Scope(['crm']))
+            ->build();
+
+        yield 'validCommand' => [
+            $applicationInstallationBuilder->getApplicationStatus(),
+            $applicationInstallationBuilder->getPortalLicenseFamily(),
+            $applicationInstallationBuilder->getPortalUsersCount(),
+            $applicationInstallationBuilder->getContactPersonId(),
+            $applicationInstallationBuilder->getBitrix24PartnerContactPersonId(),
+            $applicationInstallationBuilder->getBitrix24PartnerId(),
+            $applicationInstallationBuilder->getExternalId(),
+            $applicationInstallationBuilder->getComment(),
+            $bitrix24AccountBuilder->getBitrix24UserId(),
+            $bitrix24AccountBuilder->isBitrix24UserAdmin(),
+            $bitrix24AccountBuilder->getMemberId(),
+            new Domain($bitrix24AccountBuilder->getDomainUrl()),
+            $bitrix24AccountBuilder->getAuthToken(),
+            $bitrix24AccountBuilder->getApplicationVersion(),
+            $bitrix24AccountBuilder->getApplicationScope(),
+            null,
+            null,
+        ];
+
+        yield 'invalidPortalUsersCount' => [
+            $applicationInstallationBuilder->getApplicationStatus(),
+            $applicationInstallationBuilder->getPortalLicenseFamily(),
+            0,
+            $applicationInstallationBuilder->getContactPersonId(),
+            $applicationInstallationBuilder->getBitrix24PartnerContactPersonId(),
+            $applicationInstallationBuilder->getBitrix24PartnerId(),
+            $applicationInstallationBuilder->getExternalId(),
+            $applicationInstallationBuilder->getComment(),
+            $bitrix24AccountBuilder->getBitrix24UserId(),
+            $bitrix24AccountBuilder->isBitrix24UserAdmin(),
+            $bitrix24AccountBuilder->getMemberId(),
+            new Domain($bitrix24AccountBuilder->getDomainUrl()),
+            $bitrix24AccountBuilder->getAuthToken(),
+            $bitrix24AccountBuilder->getApplicationVersion(),
+            $bitrix24AccountBuilder->getApplicationScope(),
+            null,
+            InvalidArgumentException::class,
+        ];
+
+        yield 'emptyExternalId' => [
+            $applicationInstallationBuilder->getApplicationStatus(),
+            $applicationInstallationBuilder->getPortalLicenseFamily(),
+            $applicationInstallationBuilder->getPortalUsersCount(),
+            $applicationInstallationBuilder->getContactPersonId(),
+            $applicationInstallationBuilder->getBitrix24PartnerContactPersonId(),
+            $applicationInstallationBuilder->getBitrix24PartnerId(),
+            '',
+            $applicationInstallationBuilder->getComment(),
+            $bitrix24AccountBuilder->getBitrix24UserId(),
+            $bitrix24AccountBuilder->isBitrix24UserAdmin(),
+            $bitrix24AccountBuilder->getMemberId(),
+            new Domain($bitrix24AccountBuilder->getDomainUrl()),
+            $bitrix24AccountBuilder->getAuthToken(),
+            $bitrix24AccountBuilder->getApplicationVersion(),
+            $bitrix24AccountBuilder->getApplicationScope(),
+            null,
+            InvalidArgumentException::class,
+        ];
+
+        yield 'emptyComment' => [
+            $applicationInstallationBuilder->getApplicationStatus(),
+            $applicationInstallationBuilder->getPortalLicenseFamily(),
+            $applicationInstallationBuilder->getPortalUsersCount(),
+            $applicationInstallationBuilder->getContactPersonId(),
+            $applicationInstallationBuilder->getBitrix24PartnerContactPersonId(),
+            $applicationInstallationBuilder->getBitrix24PartnerId(),
+            $applicationInstallationBuilder->getExternalId(),
+            '',
+            $bitrix24AccountBuilder->getBitrix24UserId(),
+            $bitrix24AccountBuilder->isBitrix24UserAdmin(),
+            $bitrix24AccountBuilder->getMemberId(),
+            new Domain($bitrix24AccountBuilder->getDomainUrl()),
+            $bitrix24AccountBuilder->getAuthToken(),
+            $bitrix24AccountBuilder->getApplicationVersion(),
+            $bitrix24AccountBuilder->getApplicationScope(),
+            null,
+            InvalidArgumentException::class,
+        ];
+
+
+        yield 'invalidBitrix24UserId' => [
+            $applicationInstallationBuilder->getApplicationStatus(),
+            $applicationInstallationBuilder->getPortalLicenseFamily(),
+            $applicationInstallationBuilder->getPortalUsersCount(),
+            $applicationInstallationBuilder->getContactPersonId(),
+            $applicationInstallationBuilder->getBitrix24PartnerContactPersonId(),
+            $applicationInstallationBuilder->getBitrix24PartnerId(),
+            $applicationInstallationBuilder->getExternalId(),
+            $applicationInstallationBuilder->getComment(),
+            0,
+            $bitrix24AccountBuilder->isBitrix24UserAdmin(),
+            $bitrix24AccountBuilder->getMemberId(),
+            new Domain($bitrix24AccountBuilder->getDomainUrl()),
+            $bitrix24AccountBuilder->getAuthToken(),
+            $bitrix24AccountBuilder->getApplicationVersion(),
+            $bitrix24AccountBuilder->getApplicationScope(),
+            null,
+            InvalidArgumentException::class,
+        ];
+
+        // Пустой memberId
+        yield 'emptyMemberId' => [
+            $applicationInstallationBuilder->getApplicationStatus(),
+            $applicationInstallationBuilder->getPortalLicenseFamily(),
+            $applicationInstallationBuilder->getPortalUsersCount(),
+            $applicationInstallationBuilder->getContactPersonId(),
+            $applicationInstallationBuilder->getBitrix24PartnerContactPersonId(),
+            $applicationInstallationBuilder->getBitrix24PartnerId(),
+            $applicationInstallationBuilder->getExternalId(),
+            $applicationInstallationBuilder->getComment(),
+            $bitrix24AccountBuilder->getBitrix24UserId(),
+            $bitrix24AccountBuilder->isBitrix24UserAdmin(),
+            '',
+            new Domain($bitrix24AccountBuilder->getDomainUrl()),
+            $bitrix24AccountBuilder->getAuthToken(),
+            $bitrix24AccountBuilder->getApplicationVersion(),
+            $bitrix24AccountBuilder->getApplicationScope(),
+            null,
+            InvalidArgumentException::class,
+        ];
+
+        // Некорректная версия приложения
+        yield 'invalidApplicationVersion' => [
+            $applicationInstallationBuilder->getApplicationStatus(),
+            $applicationInstallationBuilder->getPortalLicenseFamily(),
+            $applicationInstallationBuilder->getPortalUsersCount(),
+            $applicationInstallationBuilder->getContactPersonId(),
+            $applicationInstallationBuilder->getBitrix24PartnerContactPersonId(),
+            $applicationInstallationBuilder->getBitrix24PartnerId(),
+            $applicationInstallationBuilder->getExternalId(),
+            $applicationInstallationBuilder->getComment(),
+            $bitrix24AccountBuilder->getBitrix24UserId(),
+            $bitrix24AccountBuilder->isBitrix24UserAdmin(),
+            $bitrix24AccountBuilder->getMemberId(),
+            new Domain($bitrix24AccountBuilder->getDomainUrl()),
+            $bitrix24AccountBuilder->getAuthToken(),
+            0,
+            $bitrix24AccountBuilder->getApplicationScope(),
+            null,
+            InvalidArgumentException::class,
+        ];
+
+        yield 'emptyApplicationToken' => [
+            $applicationInstallationBuilder->getApplicationStatus(),
+            $applicationInstallationBuilder->getPortalLicenseFamily(),
+            $applicationInstallationBuilder->getPortalUsersCount(),
+            $applicationInstallationBuilder->getContactPersonId(),
+            $applicationInstallationBuilder->getBitrix24PartnerContactPersonId(),
+            $applicationInstallationBuilder->getBitrix24PartnerId(),
+            $applicationInstallationBuilder->getExternalId(),
+            $applicationInstallationBuilder->getComment(),
+            $bitrix24AccountBuilder->getBitrix24UserId(),
+            $bitrix24AccountBuilder->isBitrix24UserAdmin(),
+            $bitrix24AccountBuilder->getMemberId(),
+            new Domain($bitrix24AccountBuilder->getDomainUrl()),
+            $bitrix24AccountBuilder->getAuthToken(),
+            $bitrix24AccountBuilder->getApplicationVersion(),
+            $bitrix24AccountBuilder->getApplicationScope(),
+            '',
+            InvalidArgumentException::class
+        ];
+
+    }
+}
\ No newline at end of file
diff --git a/tests/Unit/ApplicationInstallations/UseCase/OnAppInstall/CommandTest.php b/tests/Unit/ApplicationInstallations/UseCase/OnAppInstall/CommandTest.php
new file mode 100644
index 0000000..fcf556b
--- /dev/null
+++ b/tests/Unit/ApplicationInstallations/UseCase/OnAppInstall/CommandTest.php
@@ -0,0 +1,109 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Bitrix24\Lib\Tests\Unit\ApplicationInstallations\UseCase\OnAppInstall;
+
+use Bitrix24\Lib\ApplicationInstallations\UseCase\OnAppInstall\Command;
+use Bitrix24\Lib\Bitrix24Accounts\ValueObjects\Domain;
+use Bitrix24\Lib\Tests\Functional\ApplicationInstallations\Builders\ApplicationInstallationBuilder;
+use Bitrix24\Lib\Tests\Functional\Bitrix24Accounts\Builders\Bitrix24AccountBuilder;
+use Bitrix24\SDK\Application\ApplicationStatus;
+use Bitrix24\SDK\Application\Contracts\ApplicationInstallations\Entity\ApplicationInstallationStatus;
+use Bitrix24\SDK\Application\Contracts\Bitrix24Accounts\Entity\Bitrix24AccountStatus;
+use Bitrix24\SDK\Application\PortalLicenseFamily;
+use Bitrix24\SDK\Core\Credentials\Scope;
+use PHPUnit\Framework\Attributes\CoversClass;
+use PHPUnit\Framework\TestCase;
+use PHPUnit\Framework\Attributes\DataProvider;
+use PHPUnit\Framework\Attributes\Test;
+use Symfony\Component\Uid\Uuid;
+
+/**
+ * @internal
+ */
+#[CoversClass(Command::class)]
+class CommandTest extends TestCase
+{
+    #[Test]
+    #[DataProvider('dataForCommand')]
+    public function testValidCommand(
+        string  $memberId,
+        Domain  $domain,
+        string  $applicationToken,
+        string  $applicationStatus,
+        ?string $expectedException,
+    ): void
+    {
+        if (null !== $expectedException) {
+            $this->expectException($expectedException);
+        }
+
+        $command = new Command(
+            $memberId,
+            $domain,
+            $applicationToken,
+            $applicationStatus
+        );
+
+        if (null === $expectedException) {
+            $this->assertInstanceOf(Command::class, $command);
+        }
+    }
+
+    public static function dataForCommand(): \Generator
+    {
+        $applicationToken = Uuid::v7()->toRfc4122();
+        $applicationStatus = 'T';
+
+        (new ApplicationInstallationBuilder())
+            ->withApplicationStatus(new ApplicationStatus('F'))
+            ->withPortalLicenseFamily(PortalLicenseFamily::free)
+            ->withApplicationToken($applicationToken)
+            ->withApplicationStatusInstallation(ApplicationInstallationStatus::active)
+            ->build();
+
+        $bitrix24AccountBuilder = (new Bitrix24AccountBuilder())
+            ->withApplicationScope(new Scope(['crm']))
+            ->withInstalled()
+            ->withApplicationToken($applicationToken)
+            ->withStatus(Bitrix24AccountStatus::active)
+            ->build();
+
+        // Валидный кейс
+        yield 'validCommand' => [
+            $bitrix24AccountBuilder->getMemberId(),
+            new Domain($bitrix24AccountBuilder->getDomainUrl()),
+            $applicationToken,
+            $applicationStatus,
+            null,
+        ];
+
+        // Пустой memberId
+        yield 'emptyMemberId' => [
+            '',
+            new Domain($bitrix24AccountBuilder->getDomainUrl()),
+            $applicationToken,
+            $applicationStatus,
+            \InvalidArgumentException::class,
+        ];
+
+        // Пустой applicationToken
+        yield 'emptyApplicationToken' => [
+            $bitrix24AccountBuilder->getMemberId(),
+            new Domain($bitrix24AccountBuilder->getDomainUrl()),
+            '',
+            $applicationStatus,
+            \InvalidArgumentException::class,
+        ];
+
+        // Пустой applicationStatus
+        yield 'emptyApplicationStatus' => [
+            $bitrix24AccountBuilder->getMemberId(),
+            new Domain($bitrix24AccountBuilder->getDomainUrl()),
+            $applicationToken,
+            '',
+            \InvalidArgumentException::class,
+        ];
+    }
+}
\ No newline at end of file
diff --git a/tests/Unit/ApplicationInstallations/UseCase/Uninstall/CommandTest.php b/tests/Unit/ApplicationInstallations/UseCase/Uninstall/CommandTest.php
new file mode 100644
index 0000000..97fd0d7
--- /dev/null
+++ b/tests/Unit/ApplicationInstallations/UseCase/Uninstall/CommandTest.php
@@ -0,0 +1,83 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Bitrix24\Lib\Tests\Unit\ApplicationInstallations\UseCase\Uninstall;
+
+use Bitrix24\Lib\ApplicationInstallations\UseCase\Uninstall\Command;
+use Bitrix24\Lib\Bitrix24Accounts\ValueObjects\Domain;
+use Bitrix24\Lib\Tests\Functional\Bitrix24Accounts\Builders\Bitrix24AccountBuilder;
+use Bitrix24\SDK\Application\Contracts\Bitrix24Accounts\Entity\Bitrix24AccountStatus;
+use Bitrix24\SDK\Core\Credentials\Scope;
+use PHPUnit\Framework\Attributes\CoversClass;
+use PHPUnit\Framework\TestCase;
+use PHPUnit\Framework\Attributes\DataProvider;
+use PHPUnit\Framework\Attributes\Test;
+use Symfony\Component\Uid\Uuid;
+
+/**
+ * @internal
+ */
+#[CoversClass(Command::class)]
+class CommandTest extends TestCase
+{
+    #[Test]
+    #[DataProvider('dataForCommand')]
+    public function testValidCommand(
+        string  $memberId,
+        Domain  $domain,
+        string  $applicationToken,
+        ?string $expectedException,
+    ): void
+    {
+        if (null !== $expectedException) {
+            $this->expectException($expectedException);
+        }
+
+        $command = new Command(
+            $domain,
+            $memberId,
+            $applicationToken
+        );
+
+        if (null === $expectedException) {
+            $this->assertInstanceOf(Command::class, $command);
+        }
+    }
+
+    public static function dataForCommand(): \Generator
+    {
+        $applicationToken = Uuid::v7()->toRfc4122();
+
+        $bitrix24AccountBuilder = (new Bitrix24AccountBuilder())
+            ->withApplicationScope(new Scope(['crm']))
+            ->withInstalled()
+            ->withApplicationToken($applicationToken)
+            ->withStatus(Bitrix24AccountStatus::active)
+            ->build();
+
+        // Валидный кейс
+        yield 'validCommand' => [
+            $bitrix24AccountBuilder->getMemberId(),
+            new Domain($bitrix24AccountBuilder->getDomainUrl()),
+            $applicationToken,
+            null,
+        ];
+
+        // Пустой memberId
+        yield 'emptyMemberId' => [
+            '',
+            new Domain($bitrix24AccountBuilder->getDomainUrl()),
+            $applicationToken,
+            \InvalidArgumentException::class,
+        ];
+
+        // Пустой applicationToken
+        yield 'emptyApplicationToken' => [
+            $bitrix24AccountBuilder->getMemberId(),
+            new Domain($bitrix24AccountBuilder->getDomainUrl()),
+            '',
+            \InvalidArgumentException::class,
+        ];
+    }
+}
\ No newline at end of file
diff --git a/tests/Unit/Bitrix24Accounts/Entity/Bitrix24AccountTest.php b/tests/Unit/Bitrix24Accounts/Entity/Bitrix24AccountTest.php
index 3671674..66d5bf3 100644
--- a/tests/Unit/Bitrix24Accounts/Entity/Bitrix24AccountTest.php
+++ b/tests/Unit/Bitrix24Accounts/Entity/Bitrix24AccountTest.php
@@ -34,12 +34,10 @@ protected function createBitrix24AccountImplementation(
         Uuid $uuid,
         int $bitrix24UserId,
         bool $isBitrix24UserAdmin,
+        bool $isMasterAccount,
         string $memberId,
         string $domainUrl,
-        Bitrix24AccountStatus $bitrix24AccountStatus,
         AuthToken $authToken,
-        CarbonImmutable $createdAt,
-        CarbonImmutable $updatedAt,
         int $applicationVersion,
         Scope $applicationScope
     ): Bitrix24AccountInterface {
@@ -49,12 +47,10 @@ protected function createBitrix24AccountImplementation(
             $isBitrix24UserAdmin,
             $memberId,
             $domainUrl,
-            $bitrix24AccountStatus,
             $authToken,
-            $createdAt,
-            $updatedAt,
             $applicationVersion,
-            $applicationScope
+            $applicationScope,
+            $isMasterAccount
         );
     }
 }
diff --git a/tests/Unit/Bitrix24Accounts/UseCase/ChangeDomainUrl/CommandTest.php b/tests/Unit/Bitrix24Accounts/UseCase/ChangeDomainUrl/CommandTest.php
index bb3646f..d5d023a 100644
--- a/tests/Unit/Bitrix24Accounts/UseCase/ChangeDomainUrl/CommandTest.php
+++ b/tests/Unit/Bitrix24Accounts/UseCase/ChangeDomainUrl/CommandTest.php
@@ -54,16 +54,6 @@ public function testValidateInvalidDomain(
     public static function dataForValidateValidDomain(): \Generator
     {
 
-        // Примеры допустимых доменов
-        /*$arrValidDomains = [
-            ['oldDomain' => 'example.com', 'newDomain' => 'example.org'],
-            ['oldDomain' => 'пример.рф', 'newDomain' => 'пример.рус'],
-            ['oldDomain' => 'test-site.org', 'newDomain' => 'test-site.ru'],
-            ['oldDomain' => 'valid-domain.co.uk', 'newDomain' => 'valid-domain.net'],
-            ['oldDomain' => 'subdomain.example.com', 'newDomain' => 'subdomain2.example.com'],
-            ['oldDomain' => 'тест.рус', 'newDomain' => 'тест2.рус'], // Пример с кириллицей
-        ];*/
-
         yield 'validDomain1' => [
             'example.com',
             'example.org',
diff --git a/tests/Unit/Bitrix24Accounts/UseCase/InstallStart/CommandTest.php b/tests/Unit/Bitrix24Accounts/UseCase/InstallStart/CommandTest.php
index 3369550..d9d3b05 100644
--- a/tests/Unit/Bitrix24Accounts/UseCase/InstallStart/CommandTest.php
+++ b/tests/Unit/Bitrix24Accounts/UseCase/InstallStart/CommandTest.php
@@ -80,7 +80,7 @@ public static function dataForCommand(): \Generator
             'Member ID must be a non-empty string.'
         ];
 
-        yield 'validDomainUrl' => [
+        yield 'emptyDomainUrl' => [
             $bitrix24Account->getId(),
             $bitrix24Account->getBitrix24UserId(),
             $bitrix24Account->isBitrix24UserAdmin(),
@@ -93,7 +93,7 @@ public static function dataForCommand(): \Generator
             sprintf('Invalid domain: %s', '')
         ];
 
-        yield 'validBitrix24UserId' => [
+        yield 'invalidBitrix24UserId' => [
             $bitrix24Account->getId(),
             0,
             $bitrix24Account->isBitrix24UserAdmin(),
@@ -106,7 +106,7 @@ public static function dataForCommand(): \Generator
             'Bitrix24 User ID must be a positive integer.'
         ];
 
-        yield 'validApplicationToken' => [
+        yield 'invalidApplicationVersion' => [
             $bitrix24Account->getId(),
             $bitrix24Account->getBitrix24UserId(),
             $bitrix24Account->isBitrix24UserAdmin(),