Enhancing Appium Android Tests with Advanced Techniques

Raj Varma from Bumble's engineering team reveals how to give your Appium tests superpowers. His solution lets test code directly call methods inside your Android app—solving problems that seemed impossible.

Appium tests run completely separate from app code, creating major limitations. Varma engineered a 'backdoor' approach that instruments the app with a modified Appium server, allowing tests to invoke app methods via Java reflection. This enables control over unpredictable app behavior and mocking of features Appium doesn't support.

Key Takeaways

• Modified Appium UiAutomator2 server runs in same process as app under test
• Tests can disable random popups, mock device shake, and control A/B test variants
• Custom /backdoor endpoint invokes app methods using Java reflection APIs
• Solution requires one time setup: instrument app, sign with same keystore, replace bundled APK

The article includes real production examples from Bumble, plus a warning about the responsibility that comes with this much testing power.