TestFlight makes it easy to test beta versions of iOS, tvOS, and watchOS apps and provide valuable feedback to developers before they release their apps on the App Store. To become a tester, simply follow a developer’s public link or the link in an email invitation a developer sent you. TestFlight will open so you can accept your invitation to install the developer’s app.
When you test a beta app, Apple will collect and send crash logs, usage information, and any feedback you submit to the developer. The developer may use this information to improve their app and related products. Apple may use crash logs and usage information to improve our products and services.
For instructions on installation, testing, and feedback submission and for details on how your data is handled, see testflight.apple.com.