diff --git a/CHANGELOG.md b/CHANGELOG.md
index 3fbd77bb..101efc08 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,6 @@
+## 4.0.0
+* From now Qonversion supports Google Play Billing Library 4.0.0 version for Android.
+
 ## 3.3.0
 * Add `purchaseProduct()`, `updatePurchaseWithProduct()`
 * Deprecate `resetUser()`
diff --git a/README.md b/README.md
index 37a5009c..340d746c 100644
--- a/README.md
+++ b/README.md
@@ -18,7 +18,7 @@ Qonversion is the data platform to power in-app subscription revenue growth.
 </p>
 
 [![pub](https://img.shields.io/pub/v/qonversion_flutter)](https://pub.dev/packages/qonversion_flutter)
-[![MIT License](http://img.shields.io/cocoapods/l/Qonversion.svg?style=flat)](https://qonversion.io)
+[![MIT License](https://img.shields.io/cocoapods/l/Qonversion.svg?style=flat)](https://qonversion.io)
 
 
 ## How It Works: Product Center
@@ -44,10 +44,10 @@ Monitor your in-app revenue metrics. Understand your customers and make better d
 
 ## Integrations
 
-Send subscription data to your favorite platforms Share your mobile and web subscription data using our powerful integrations.
+Send subscription data to your favorite platforms. Share your mobile and web subscription data using our powerful integrations.
 
 <p align="center">
-     <a href="https://documentation.qonversion.io/docs/integrations-overview"><img width="90%", src="https://qcdn3.sfo3.digitaloceanspaces.com/github/integrations.png">
+     <a href="https://documentation.qonversion.io/docs/integrations-overview"><img width="90%" src="https://qcdn3.sfo3.digitaloceanspaces.com/github/integrations.png">
      </a>
 </p>
 
@@ -101,7 +101,7 @@ Whether you’re a core user or trying it out for the first time, you can make a
 
 * sending us feedback about something you thought was confusing or simply missing
 * sending us a pull request via GitHub
-* suggesting better wording or ways of explaining certain topics in the [Qonversion documentation](http://documentation.qonversion.io). Use `SUGGEST EDITS` button in the top right corner.
+* suggesting better wording or ways of explaining certain topics in the [Qonversion documentation](https://documentation.qonversion.io). Use `SUGGEST EDITS` button in the top right corner.
 
 ## Contributing
 
diff --git a/android/build.gradle b/android/build.gradle
index 54a4573e..59f3e3df 100644
--- a/android/build.gradle
+++ b/android/build.gradle
@@ -1,9 +1,9 @@
 group 'com.qonversion.flutter.sdk.qonversion_flutter_sdk'
-version '3.3.0'
+version '4.0.0'
 
 buildscript {
     ext.kotlin_version = '1.3.50'
-    ext.qonversion_version = '2.9.1'
+    ext.qonversion_version = '3.0.0'
     repositories {
         google()
         jcenter()
diff --git a/lib/src/models/sk_product/subscription_period.dart b/lib/src/models/sk_product/subscription_period.dart
index c58a0fe6..26cadb41 100644
--- a/lib/src/models/sk_product/subscription_period.dart
+++ b/lib/src/models/sk_product/subscription_period.dart
@@ -36,7 +36,8 @@ class SKProductSubscriptionPeriodWrapper {
     return _$SKProductSubscriptionPeriodWrapperFromJson(map);
   }
 
-  Map<String, dynamic> toJson() => _$SKProductSubscriptionPeriodWrapperToJson(this);
+  Map<String, dynamic> toJson() =>
+      _$SKProductSubscriptionPeriodWrapperToJson(this);
 
   @override
   bool operator ==(Object other) {
diff --git a/lib/src/qonversion.dart b/lib/src/qonversion.dart
index 3432cbba..65a7f07e 100644
--- a/lib/src/qonversion.dart
+++ b/lib/src/qonversion.dart
@@ -16,7 +16,7 @@ import 'models/purchase_exception.dart';
 import 'qa_provider.dart';
 
 class Qonversion {
-  static const String _sdkVersion = "3.3.0";
+  static const String _sdkVersion = "4.0.0";
 
   static const MethodChannel _channel = MethodChannel('qonversion_flutter_sdk');
 
@@ -70,9 +70,11 @@ class Qonversion {
 
   /// Call this function to reset user ID and generate new anonymous user ID.
   /// Call this function before Qonversion.launch()
-  @Deprecated("This function was used in debug mode only. You can reinstall the app if you need to reset the user ID.")
+  @Deprecated(
+      "This function was used in debug mode only. You can reinstall the app if you need to reset the user ID.")
   static Future<void> resetUser() async {
-    debugPrint("resetUser() function is deprecated now. It was used in debug mode only. You can reinstall the app if you need to reset the user ID.");
+    debugPrint(
+        "resetUser() function is deprecated now. It was used in debug mode only. You can reinstall the app if you need to reset the user ID.");
   }
 
   /// This method will send all purchases to the Qonversion backend. Call this every time when purchase is handled by you own implementation.
diff --git a/pubspec.lock b/pubspec.lock
index 50ce9831..2e23f9bb 100644
--- a/pubspec.lock
+++ b/pubspec.lock
@@ -119,7 +119,7 @@ packages:
       name: cli_util
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "0.3.0"
+    version: "0.3.2"
   clock:
     dependency: transitive
     description:
@@ -147,7 +147,7 @@ packages:
       name: convert
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "3.0.0"
+    version: "3.0.1"
   crypto:
     dependency: transitive
     description:
@@ -227,7 +227,7 @@ packages:
       name: io
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.0.0"
+    version: "1.0.2"
   js:
     dependency: transitive
     description:
diff --git a/pubspec.yaml b/pubspec.yaml
index 587f0342..9d160169 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -1,6 +1,6 @@
 name: qonversion_flutter
 description: Flutter plugin to implement in-app subscriptions and purchases. Validate user receipts and manage cross-platform access to paid content on your app. Android & iOS.
-version: 3.3.0
+version: 4.0.0
 homepage: 'https://qonversion.io'
 repository: 'https://github.com/qonversion/flutter-sdk'