This skill should be used when the user asks to "build an Android app", "create a Composable", "set up an Android project", "review Android code", "refactor Android", "add a screen", "create a Wear OS app", "build for Android TV", "build for Android Auto", "build for Android Automotive", "adapt for Meta Quest", "build for Fire TV", "build for Fire Tablet", "set up Room database", "add local storage", "use DataStore", "persist data", "add database migration", "encrypt storage", "add in-app purchases", "integrate Google Play Billing", "add subscriptions", "implement billing", "monetize app", "write Android tests", "test ViewModel", "test Composable", "set up Android testing", "add unit tests", "configure Android Lint", "add custom lint rule", "set up lint baseline", or when generating any Kotlin code targeting Google/Android platforms (including AOSP-based devices). Provides modern Jetpack Compose-first best practices covering UI patterns, app lifecycle, navigation, local storage, billing/payments, testing, Android Lint, and platform-specific guidance. Use together with `kotlin-development` for language fundamentals. Always generates Kotlin unless the project explicitly requires Java.