Definition: Beta testing is releasing an early version of an app to a limited group of real users before the full release, to gather feedback on how it works in real conditions. In the mobile test pyramid it forms its own layer between end-to-end and unit testing.
So what? Mobile users have high expectations and little patience. Beta testing exposes problems that only appear on real devices, networks and usage patterns, while there's still time to fix them.
Examples: Inviting a group of customers to try an app's next version before it goes to the app store. Asking colleagues across the company to use an early build and report problems.
