Android Developer
Interview Guide

Jetpack Compose is now the preferred UI toolkit for new Android development. Google has invested heavily in Compose and recommends it for new projects. However, most large codebases (LinkedIn, Airbnb, Google's own apps) use a hybrid approach: Compose for new screens, View system for existing screens. Senior engineers need both.

MVVM (Model-View-ViewModel) with Clean Architecture layers (presentation, domain, data) is the industry standard. MVI (Model-View-Intent) is growing for Compose-first apps. Google's Architecture Guide (unidirectional data flow with ViewModel and UI state) is the recommended reference for interview discussions.

Very important for senior roles. Know: startup time optimization (app launch, cold/warm/hot), rendering performance (jank detection with systrace), memory profiling (avoiding memory leaks, LeakCanary), battery optimization (WorkManager for background work, power profiler), and network optimization (OkHttp interceptors, response caching).

StateFlow is a hot flow with a single current value (like LiveData) — always has a value, replays the last value to new collectors. SharedFlow is a more configurable hot flow — can replay N items, buffer events, and emit to multiple collectors without requiring a value. Use StateFlow for UI state; use SharedFlow for one-time events (navigation, snackbars) where you don't want state replay.