You’ve created your app in Xcode and optionally added app services. You’ve tested your app in a device simulator and on your own devices. It’s time to distribute your app to a wider audience—to give the app a “real-world” test and, in some cases, to offer users a preview of your next version.
Let Apple distribute your prerelease app for you using TestFlight. You upload your app to iTunes Connect, as described in Uploading Your App to iTunes Connect, and then use iTunes Connect to invite testers. Optionally, distribute your app to 25 internal testers (your iTunes Connect users) or 2000 external testers per app (users with email addresses). Testers download and install thinned variants of your app using the TestFlight app available on the store. Apple provides a crash report service, described in Analyzing Crash Reports, that allows you to view crash reports directly in Xcode for apps distributed using TestFlight.
If you invite internal testers only, your app is not submitted to Beta App Review.