Overview

The UiAutomator2 driver is an Appium driver intended for black-box automated testing of native and hybrid Android applications.

Target Platforms¶

The driver supports the following Android platforms as automation targets:

Platform	Simulators	Real devices
Android
Android TV
Android Wear / Wear OS
Android XR		¹
Android Auto
Android Automotive		¹

Contexts¶

The following application contexts are supported for automation:

Native applications
Webviews based on Chrome
Hybrid applications

Technologies Used¶

The UiAutomator2 driver uses the W3C WebDriver protocol for session management. Under the hood, the driver combines several different technologies to achieve its functionality:

Native testing
- Based on Android's UI Automator library
- Provided by the appium-uiautomator2-server library
Webview testing
- Based on the ChromeDriver server
- Provided by the appium-chromedriver library
Additional tools
- Support for adb is handled by the appium-adb library
- Management of certain Android settings is handled by the io.appium.settings library

Several libraries and other features are shared with the Appium Espresso driver, as part of the appium-android-driver library.

End-to-End Architecture¶

The diagram below is intentionally the simplest end-to-end example. Cloud service providers, device farms, network gateways, and sophisticated local setups may insert additional layers between the client library and the automation host.

flowchart TD
  subgraph ClientSide["Test Client"]
    T["Test Code"]
    CL["Appium Client Library<br/>(Java / Python / JS / Ruby / C#)"]
  end

  subgraph ServerHost["Automation Host"]
    AS["Appium Server<br/>WebDriver HTTP API"]
    XD["UiAutomator2 Driver<br/>(appium-uiautomator2-driver)"]
    ADBM["ADB + Port Forwarding"]
    CDM["Chromedriver Management<br/>(hybrid / webview only)"]
  end

  subgraph DeviceTarget["Android Device / Emulator"]
    U2S["UiAutomator2 Server<br/>(instrumentation HTTP API)"]
    UIA["UiAutomator Framework"]
    CD["Chromedriver<br/>(in webview context)"]
    AUT["Application Under Test"]
  end

  T --> CL
  CL -->|"W3C WebDriver over HTTP"| AS
  AS -->|"Forwards session commands to driver"| XD
  XD -->|"Install, shell, forward ports"| ADBM
  XD -->|"Context switch to WEBVIEW_*"| CDM
  ADBM -->|"adb forward (e.g. host:8200 → device:6790)"| U2S
  CDM -->|"Chromedriver HTTP"| CD
  U2S -->|"UiAutomator APIs"| UIA
  UIA -->|"UI interactions + accessibility tree"| AUT
  CD -->|"WebDriver in webview"| AUT

Not tested ↩↩