Android development encompasses building applications for the Android platform using Android Studio IDE, Jetpack libraries, and Material Design principles. The ecosystem centers on Kotlin-first development with reactive patterns (Flow, LiveData), declarative UI (Jetpack Compose), and architecture components (ViewModel, Room) that handle lifecycle complexity and configuration changes. A key insight: Google's recommended modern stack treats the View/Compose UI layer as stateless — business logic lives in ViewModels and repositories, state flows down as immutable data, and events flow up as one-time actions.