TestFlight
You will automatically receive an invitation email to join your group of beta testers and will be prompted to install the free TestFlight app from the App Store. The TestFlight app makes installing beta apps simple, with no need to keep track of UDIDs or provisioning profiles.
For more information, read the Häufig gestellte Fragen zu TestFlight or view the TestFlight-Anwendung im App Store.