Umain Launcher

A minimal, working Android home launcher built with Kotlin + Jetpack Compose, inspired by NoLagLauncher.

It shows what actually turns an app into a launcher and keeps everything else as small as possible:

• A wallpaper-facing home screen with a live clock and a favorites dock.

• A swipe-up app drawer with a grid searchable by label or package name.

• Tap to launch; long-press for App info, copy package name, pin, hide or uninstall.

• Multi-select mode to hide or uninstall several apps at once.

• Hidden apps persist (DataStore) and can be revealed with a toggle.

• Settings (long-press the home screen, or the gear in the drawer): layout (icon grid or a Minimal AF text-only list — names, no icons), grid columns and icon size, an icon color filter (grayscale / desaturated / sepia), theme (system/light/dark + Material You), and wallpaper (system picker or pick-and-apply).

Dev/pentest oriented:

• Activity Launcher — inspect a package (version, SDK levels, debuggable/allowBackup/ system flags, permissions) and fire any of its activities directly.
• Dev shortcuts — quick chips into Developer options, Device info and Settings.

The full step-by-step tutorial lives in posts/ — in English and Português-BR.

Requirements

Verified against the current stable toolchain (July 2026):

Tool	Version
Android Studio	Quail 1 (2026.1.1) or newer
Android Gradle Plugin (AGP)	9.2.1
Gradle	9.6.1
Kotlin	2.4.10 (bundled via AGP's built-in Kotlin)
Compose BOM	2026.06.01
JDK	17+ (the bundled Android Studio JBR works)
compileSdk / targetSdk	37 · minSdk 26 (Android 8.0+)
SDK Build Tools	36.0.0

Run it

1. Open the project in Android Studio and let it sync.
2. Run the app configuration on an emulator or device.
3. Press the Home button and pick Umain Launcher → Always.

From the command line (SDK configured in local.properties):

./gradlew installDebug

To go back to your normal launcher: Settings → Apps → Default apps → Home app.

Project layout

app/src/main/
├── AndroidManifest.xml           # HOME intent-filter + <queries> — this is what makes it a launcher
├── java/com/umain/launcher/
│   ├── MainActivity.kt           # single Activity, hosts Compose
│   ├── data/
│   │   ├── AppInfo.kt            # one launchable app
│   │   └── AppRepository.kt      # queries + launches apps via PackageManager
│   └── ui/
│       ├── HomeViewModel.kt      # holds the app list (StateFlow)
│       ├── LauncherRoot.kt       # home + drawer composition
│       ├── HomeScreen.kt         # clock + swipe-up gesture
│       ├── AppDrawer.kt          # searchable app grid
│       └── theme/                # Material 3 theme
└── res/                          # icons, strings, launcher theme (transparent → wallpaper shows)

License

Sample/demo code for the accompanying blog post. Use freely.