UiAutomator2

UIAutomator2 is an Android UI testing framework that enables automated interaction with the user interface across apps and the system. It serves as an evolution of the original UIAutomator framework, offering improved stability and cross-app testing on modern Android devices. Tests using UIAutomator2 can simulate user actions such as taps, swipes, text input, and navigation, and they can inspect properties of visible UI controls.

The framework operates with a client-server architecture. A test APK on the host installs and communicates with a server component (uiautomator2-server) running on the device. The host test code uses APIs from the AndroidX Test UIAutomator library to obtain a reference to a device object and to locate UI elements. Interactions are performed through a JSON-RPC style channel over ADB, enabling control over elements in the app under test as well as in system UI.

Key capabilities include cross-app automation, access to system UI, and the ability to interact with elements across different applications. This makes UIAutomator2 suitable for end-to-end flows that involve multiple apps or the device’s home screen. It is commonly used as the Android backend for Appium, where the UiAutomator2 driver enables automated tests to run on real devices and emulators while supporting multi-app scenarios.

Limitations include reliance on instrumented testing on devices, potential flakiness with dynamic UIs, and slower execution compared to in-app testing frameworks for some tasks. It is typically employed for large-scale UI validation, compatibility testing, and end-to-end scenarios across apps.