You can manage your team's testers and distribute builds to them using the Firebase console.
To distribute your app to testers, upload the IPA file using the Firebase console:
Open the App Distribution page of the Firebase console. Select your Firebase project when prompted.
On the Releases page, select the app you want to distribute from the drop-down menu.
Drag your app's IPA file to the console to upload it.
When the upload completes, specify the tester groups and individual testers you want to receive the build. Then, add release notes for the build.
See Manage testers for more on creating tester groups.
Click Distribute to make the build available to testers.
To share links to specific releases with testers who have access to those releases, click the Link icon to copy the release link to the clipboard.
Once you distribute your build, it becomes available in the App Distribution dashboard of the Firebase console for 150 days (five months). When the build is 30 days from expiring, an expiration notice appears in both the Firebase console and your tester's list of builds on their test device.
Testers who haven't been invited to test the app receive email invitations to get started, and existing testers receive email notifications that a new build is ready to test. To learn how to install the test app, see Get set up as a tester. You can monitor the status of each tester-whether they accepted the invitation and whether they downloaded the app-in the Firebase console.
Testers have 30 days to accept an invitation to test the app before it expires. When an invitation is 5 days from expiring, an expiration notice appears in the Firebase console next to the tester on a release. An invitation can be renewed by resending it using the drop-down menu on the tester row.
To register more devices manually or programmatically, see Register additional iOS devices.
Learn best practices for distributing Apple apps to QA testers using CI/CD and fastlane.