Android Kotlin Compose Development
Create production-quality Android applications following Google's official architecture guidance and best practices. Use when building Android apps with Kotlin, Jetpack Compose, MVVM architecture, Hilt dependency injection, Room database, or Android multi-module projects. Triggers on requests to create Android projects, screens, ViewModels, repositories, feature modules, or when asked about Android architecture patterns.
Quick Reference
| Task | Reference File |
|---|---|
| Project structure & modules | modularization.md |
| Architecture layers (Presentation, Domain, Data, UI) | architecture.md |
| Compose patterns, animation, effects, modifiers | compose-patterns.md |
| Accessibility & TalkBack support | android-accessibility.md |
| Notifications & foreground services | android-notifications.md |
| Data sync & offline-first patterns | android-data-sync.md |
| Material 3 theming & dynamic colors | android-theming.md |
| Navigation3 & adaptive navigation | android-navigation.md |
| Kotlin best practices | kotlin-patterns.md |
| Coroutines best practices | coroutines-patterns.md |
| Gradle & build configuration | gradle-setup.md |
| Testing approach | testing.md |
| Internationalization & localization | android-i18n.md |
| Icons, graphics, and custom drawing | android-graphics.md |
| Runtime permissions | android-permissions.md |
| Kotlin delegation patterns | kotlin-delegation.md |
| Crash reporting | crashlytics.md |
| StrictMode guardrails | android-strictmode.md |
| Multi-module dependencies | dependencies.md |
| Code quality (Detekt) | code-quality.md |
| Code coverage (JaCoCo) | android-code-coverage.md |
| Security (encryption, biometrics, pinning) | android-security.md |
| Design patterns | design-patterns.md |
| Android performance, recomposition & app startup | android-performance.md |
| Debugging (Logcat, ANR, R8, memory leaks) | android-debugging.md |
| Migration guides (XML, RxJava, Navigation, Compose) | migration.md |
Workflow Decision Tree
Creating a new project? → Start with assets/settings.gradle.kts.template for settings and module includes → Start with assets/libs.versions.toml.template for the version catalog → Copy all files from assets/convention/ to build-logic/convention/src/main/kotlin/ → Create build-logic/settings.gradle.kts (see assets/convention/QUICK_REFERENCE.md) → Add includeBuild("build-logic") to root settings.gradle.kts → Add plugin entries to gradle/libs.versions.toml (see assets/convention/QUICK_REFERENCE.md) → Copy assets/proguard-rules.pro.template to app/proguard-rules.pro → Read modularization.md for structure and module types → Use gradle-setup.md for build files and build logic
Configuring Gradle/build files? → Use gradle-setup.md for module build.gradle.kts patterns → Use gradle-setup.md → "Build Performance" for optimization workflow, diagnostics, and bottleneck troubleshooting → Copy convention plugins from assets/convention/ to build-logic/ in your project → See assets/convention/QUICK_REFERENCE.md for setup instructions and examples → Copy assets/proguard-rules.pro.template to app/proguard-rules.pro for R8 rules
Setting up code quality / Detekt? → Use code-quality.md for Detekt convention plugin setup → Start from assets/detekt.yml.template for rules and enable Compose rules
Adding or updating dependencies? → Follow dependencies.md → Update assets/libs.versions.toml.template if the dependency is missing
Adding a new feature/module? → Follow module naming in modularization.md → Implement Presentation in the feature module → Follow dependency flow: Feature → Core/Domain → Core/Data
Building UI screens/components? → Read compose-patterns.md for screen architecture, state, components, modifiers → Use android-theming.md for Material 3 colors, typography, and shapes → Always align Kotlin code with kotlin-patterns.md → Create Screen + ViewModel + UiState in the feature module → Use shared components from core/ui when possible
Setting up app theme (colors, typography, shapes)? → Follow android-theming.md for Material 3 theming and dynamic colors → Use semantic color roles from MaterialTheme.colorScheme (never hardcoded colors) → Support light/dark themes with user preference toggle → Enable dynamic color (Material You) for API 31+
Writing any Kotlin code? → Always follow kotlin-patterns.md → Ensure practices align with architecture.md, modularization.md, and compose-patterns.md
Setting up data/domain layers? → Read architecture.md → Create Repository interfaces in core/domain → Implement Repository in core/data → Create DataSource + DAO in core/data
Implementing offline-first or data synchronization? → Follow android-data-sync.md for sync strategies, conflict resolution, and cache invalidation → Use Room as single source of truth with sync metadata (syncStatus, lastModified) → Schedule background sync with WorkManager → Monitor network state before syncing
Setting up navigation? → Follow android-navigation.md for Navigation3 architecture, state management, and adaptive navigation → See modularization.md for feature module navigation components (Destination, Navigator, Graph) → Configure navigation graph in the app module → Use feature navigation destinations and navigator interfaces
Adding tests? → Use testing.md for patterns and examples → Use testing.md → "Screenshot Testing" for Compose Preview Screenshot Testing setup → Keep test doubles in core/testing
Handling runtime permissions? → Follow android-permissions.md for manifest declarations and Compose permission patterns → Request permissions contextually and handle "Don't ask again" flows
Showing notifications or foreground services? → Use android-notifications.md for notification channels, styles, actions, and foreground services → Check POST_NOTIFICATIONS permission on API 33+ before showing notifications → Create notification channels at app startup (required for API 26+)
Sharing logic across ViewModels or avoiding base classes? → Use delegation via interfaces as described in kotlin-delegation.md → Prefer small, injected delegates for validation, analytics, or feature flags
Adding crash reporting / monitoring? → Follow crashlytics.md for provider-agnostic interfaces and module placement → Use DI bindings to swap between Firebase Crashlytics or Sentry
Enabling StrictMode guardrails? → Follow android-strictmode.md for app-level setup and Compose compiler diagnostics → Use Sentry/Firebase init from crashlytics.md to ship StrictMode logs
Choosing design patterns for a new feature, business logic, or system? → Use design-patterns.md for Android-focused pattern guidance → Align with architecture.md and modularization.md
Measuring performance regressions or startup/jank? → Use android-performance.md for Macrobenchmark, Baseline Profiles, and ProfileInstaller setup → Keep benchmark module aligned with benchmark build type in gradle-setup.md → If the user explicitly requests to investigate jank or add custom trace points, use android-performance.md for System Tracing (androidx.tracing) setup
Setting up app initialization or splash screen? → Follow android-performance.md → "App Startup & Initialization" for App Startup library, lazy init, and splash screen → Avoid ContentProvider-based auto-initialization - use Initializer interface instead → Use installSplashScreen() with setKeepOnScreenCondition for loading state
Adding icons, images, or custom graphics? → Use android-graphics.md for Material Symbols icons and custom drawing → Download icons via Iconify API or Google Fonts (avoid deprecated Icons.Default.* library) → Use Modifier.drawWithContent, drawBehind, or drawWithCache for custom graphics
Creating custom UI effects (glow, shadows, gradients)? → Check android-graphics.md for Canvas drawing, BlendMode, and Palette API patterns → Use rememberInfiniteTransition for animated effects
Ensuring accessibility compliance (TalkBack, touch targets, color contrast)? → Follow android-accessibility.md for semantic properties and WCAG guidelines → Provide contentDescription for all icons and images → Ensure 48dp × 48dp minimum touch targets → Test with TalkBack and Accessibility Scanner
Working with images and color extraction? → Use android-graphics.md → "Image Loading with Coil3" for AsyncImage, SubcomposeAsyncImage, rememberAsyncImagePainter, and Hilt ImageLoader setup → Use android-graphics.md for Palette API and color extraction
Implementing complex coroutine flows or background work? → Follow coroutines-patterns.md for structured concurrency patterns → Use appropriate dispatchers (IO, Default, Main) and proper cancellation handling → Prefer StateFlow/SharedFlow over channels for state management → Use callbackFlow to wrap Android callback APIs (connectivity, sensors, location) into Flow → Use suspendCancellableCoroutine for one-shot callbacks (Play Services tasks, biometrics) → Use combine() to merge multiple Flows in ViewModels, shareIn to share expensive upstream → Handle backpressure with buffer, conflate, debounce, or sample
Need to share behavior across multiple classes? → Use kotlin-delegation.md for interface delegation patterns → Avoid base classes; prefer composition with delegated interfaces → Examples: Analytics, FormValidator, CrashReporter
Refactoring existing code or improving architecture? → Review architecture.md for layer responsibilities → Check design-patterns.md for applicable patterns → Follow kotlin-patterns.md for Kotlin-specific improvements → Ensure compliance with modularization.md dependency rules
Debugging crashes, ANRs, or obfuscated stack traces? → Follow android-debugging.md for Logcat, ANR traces, and Compose recomposition debugging → Use android-debugging.md for R8 mapping files and manual de-obfuscation → See gradle-setup.md for R8 build configuration and keep rules
Debugging performance issues or memory leaks? → Enable android-strictmode.md for development builds → Use android-performance.md for profiling and benchmarking → Use android-debugging.md for LeakCanary and heap dump analysis → Check coroutines-patterns.md for coroutine cancellation patterns
Setting up CI/CD or code quality checks? → Use code-quality.md for Detekt baseline and CI integration → Use gradle-setup.md for build cache and convention plugins → Use testing.md for test organization and coverage
Handling sensitive data or privacy concerns? → Follow crashlytics.md for data scrubbing patterns → Use android-permissions.md for proper permission justification → Check android-strictmode.md for detecting cleartext network traffic
Migrating legacy code (LiveData, Fragments, Accompanist, RxJava)? → Use migration.md for all migration paths → Follow architecture.md for modern MVVM patterns
Adding Compose animations? → Use compose-patterns.md → "Animation" for AnimatedVisibility, AnimatedContent, animate*AsState, Animatable, shared elements → Use graphicsLayer for GPU-accelerated transforms (no recomposition) → Always provide label parameter for Layout Inspector debugging
Using side effects (LaunchedEffect, DisposableEffect)? → Use compose-patterns.md → "Side Effects" for effect selection guide → LaunchedEffect(key) for state-driven coroutines, rememberCoroutineScope for event-driven → DisposableEffect for listener/resource cleanup, always include onDispose → LifecycleResumeEffect for onResume/onPause work (camera, media), LifecycleStartEffect for onStart/onStop (location, sensors)
Working with Modifier ordering or custom modifiers? → Use compose-patterns.md → "Modifiers" for chain ordering rules and patterns → Use Modifier.Node for custom modifiers (not deprecated Modifier.composed) → Order: size → padding → drawing → interaction
Migrating from Accompanist or deprecated Compose APIs? → Use migration.md for Accompanist, Compose API, Material, and Edge-to-Edge migrations → See compose-patterns.md → "Deprecated Patterns & Migrations" for a summary list
Optimizing Compose recomposition or stability? → Use compose-patterns.md for @Immutable/@Stable annotations → Use android-performance.md → "Compose Recomposition Performance" for three phases, deferred state reads, Strong Skipping Mode → Check gradle-setup.md for Compose Compiler metrics and stability reports → Use kotlin-patterns.md for immutable data structures
Working with databases (Room)? → Define DAOs and entities in core/database per modularization.md → Use testing.md for in-memory database testing and migration tests → Follow architecture.md for repository patterns with Room
Need internationalization/localization (i18n/l10n)? → Use android-i18n.md for string resources, plurals, and RTL support → Follow compose-patterns.md for RTL-aware Compose layouts → Use testing.md for locale-specific testing
Implementing network calls (Retrofit)? → Use architecture.md → "Network Layer Setup" for Retrofit service interfaces, Hilt NetworkModule, and AuthInterceptor → Define API interfaces in core/network per modularization.md → Follow dependencies.md for Retrofit, OkHttp, and serialization setup → Handle errors with generic Result<T> from kotlin-patterns.md
Creating custom lint rules or code checks? → Use code-quality.md for Detekt custom rules → Follow gradle-setup.md for convention plugin setup → Check android-strictmode.md for runtime checks
Need code coverage reporting? → Use android-code-coverage.md for JaCoCo setup → Follow testing.md for test strategies → Check gradle-setup.md for convention plugin integration
Implementing security features (encryption, biometrics, pinning)? → Use android-security.md for comprehensive security guide → Follow android-permissions.md for runtime permissions → Check crashlytics.md for PII scrubbing and data privacy