Have you had experience testing SDKs within mobile applications? How is the integration of a new SDK tested?

Testing SDK within mobile applications involves several levels:

1. Unit tests for SDK — verify individual methods and classes of the SDK in isolation.
2. Integration tests for SDK — verify the interaction of the SDK with external services or components.
3. Testing SDK integration into a mobile application:
   • Check the correctness of integration (e.g., proper initialization, SDK method calls).
   • Ensure that the SDK does not cause crashes or memory leaks.
   • Test the application's behavior under various SDK usage scenarios.

To test the integration of a new SDK into a mobile application, typically the following are done:

• Automated UI tests (e.g., Espresso for Android or XCTest for iOS), which verify SDK usage scenarios within the app.
• Performance and stability tests to ensure the SDK does not degrade app performance.
• Manual testing on real devices and emulators.

Example: if the SDK handles authentication, tests are written to verify successful and unsuccessful login via SDK, error handling, and correct UI display.

It is also important to use mock services or stubs for external SDK calls to ensure tests are stable and reproducible.