Testing
Testing WearOS apps is different from phone testing. The screen is tiny, the interaction model is rotary input + swipe, and users expect extremely fast interactions — anything that takes more than 300ms feels slow on a watch. Horologist is Google's library for building and testing WearOS apps correctly. WearOS
Testing
Kaspresso is an Android UI test framework built on top of Espresso and UIAutomator. It solves the two biggest problems with raw Espresso: flaky tests and unreadable test code. With Kaspresso, you get a clean Kotlin DSL (via Kakao), automatic waiting and retry logic, and first-class Allure report integration. If
Testing
Jetpack Compose has its own testing APIs that don't use Espresso's view matchers. Instead, Compose tests work against the semantics tree — an accessibility-oriented representation of your UI that's separate from the rendering layer. This makes Compose tests faster and less brittle than Espresso tests
Testing
Robolectric runs Android tests on the JVM — no emulator, no device, no waiting for adb to connect. It implements Android's framework classes as JVM-compatible stubs, so your Activities, Fragments, ViewModels, and Repositories run in a regular JUnit test process. A Robolectric test suite that takes 30 seconds to
Testing
App performance isn't tested — it's measured. Android's Macrobenchmark library gives you a framework for measuring startup time, frame rendering, and custom interactions on real devices. Baseline Profiles use those measurements to pre-compile critical code paths, and Perfetto lets you trace exactly what's
Maestro
Maestro is a mobile testing framework that replaces imperative test code with declarative YAML flows. You describe what the user does — tap this, type that, assert visible — and Maestro handles synchronization, retries, and cross-platform execution. This guide covers the flow syntax, handling dynamic content, CI integration, and how Maestro compares
Appium
Appium 2.x is a significant architectural departure from Appium 1.x — drivers and plugins are now installed separately, the server is leaner, and WebdriverIO has emerged as the best client library for writing and running tests. This guide covers the complete setup for iOS and Android, element locator discovery
Detox
Detox is a gray-box E2E testing framework for React Native that eliminates flakiness by synchronizing with the app's JavaScript thread and native animation system rather than relying on sleep timers. This guide walks through complete iOS and Android setup, the synchronization model that makes Detox reliable, and CI
Android
Room is Android's recommended database library, wrapping SQLite with type-safe query builders and Kotlin coroutines support. Testing Room properly means validating DAO queries, schema migrations, and Paging 3 integration—without ever touching a real disk database. Room Testing Strategy Room provides first-class support for testing through in-memory databases:
Android
Kotlin Flow is the standard for reactive programming in Android—but testing asynchronous streams is notoriously awkward. Turbine is Cash App's library that makes Flow testing readable and deterministic. Instead of manual coroutine collection and timing hacks, you get clean, sequential assertions. Why Testing Flows Is Hard Without
Android
Koin is the lightweight dependency injection framework that dominates Android Kotlin projects. Unlike Dagger/Hilt which uses code generation, Koin operates at runtime—which means misconfigured modules fail at startup rather than compile time. Testing your Koin setup properly catches these failures before they hit production. Why Koin Testing Matters
Android
Retrofit is Android's de facto HTTP client library. Testing it properly means validating that your API service interfaces produce correct requests, handle error responses gracefully, and work with your custom call adapters and interceptors. OkHttp's MockWebServer is the tool that makes all of this possible. Why