Mobile testing is the process of testing the functionality, usability, and consistency of mobile applications across different devices, platforms, and networks.

Challenges include device fragmentation, diverse operating systems (iOS, Android), various screen sizes, resolutions, network conditions, and continuous updates.

Mobile applications can be native (built for a specific platform), web-based (accessed through a browser), or hybrid (combining native and web elements).

Challenges include handling diverse devices and OS versions, dynamic screen resolutions, and ensuring test scripts are robust to handle frequent changes.

A/B testing involves comparing two versions (A and B) of a mobile app to determine which performs better in terms of user engagement, conversion rates, or other key metrics.