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Android Jetpack Compose App

The Kinema Android client (apps/android) is a watch-optimized native application built with Jetpack Compose, Material 3 Expressive, and AndroidX Media3 ExoPlayer.

Architectural Separation​

The Android project is strictly partitioned into two Gradle modules:

  1. :core: Non-UI platform library containing OkHttp networking, PinnedTrustManager, encrypted SecureStore (AES-256-GCM via Android Keystore), and SQLite offline repositories.
  2. :app: Presentation layer containing Compose UI screens, Android 12+ predictive back gesture animations, Picture-in-Picture (PiP) controllers, and ExoPlayer integration.

Key Android Features​

1. Foreground Playback & MediaSessionService​

Playback is managed by an Android MediaSessionService (PlaybackService.kt). When the user locks their screen or switches apps:

  • Playback continues seamlessly in the background without being killed by the Android low-memory killer.
  • Lock screen displays rich media artwork, playback controls, and interactive seekbars.

2. Picture-in-Picture (PiP)​

  • Automatically enters Picture-in-Picture mode when the user swipes up to return home while a video is playing.
  • Seamlessly transitions aspect ratios to match the video dimensions (e.g. 16:9 widescreen or 2.39:1 anamorphic cinema).

3. Vertical Swipe Touch Gestures​

  • Left Edge Swipe: Adjusts screen brightness from 0% to 100%.
  • Right Edge Swipe: Adjusts audio volume. Once standard system volume hits 100%, continuing the swipe activates Android's hardware LoudnessEnhancer audio effect, boosting volume up to 200% for quiet dialogue.

4. Dual-Network Roaming​

The app registers network callbacks with Android's ConnectivityManager. When moving from home Wi-Fi to cellular data, the app automatically switches connection URLs from the local LAN address (https://192.168.1.50:3000) to the public server URL without interrupting the active playback buffer.