TestFlight allows you to generate public links that can be shared with users so they can install your app and test it even before it goes live in the App Store and becomes publicly accessible.

Below you can find a step-by-step guide on how to generate a public link for your app:

1. Open your App Store Connect Dashboard and select the app for which you would like to generate the public link. You can access your App Store Connect Dashboard here: https://appstoreconnect.apple.com/apps
   

1. Click on "TestFlight"
   

1. Now click the "+" icon on "External Testing"
   

1. Type in the name of your External Testing Group in the dialog window that will appear
   

1. Now click the newly created group, scroll to the bottom of the page, on the "Builds" area click the "+" icon and select the latest build uploaded to your account
   

1. You will be requested to fill in some details about the app and contact information for reporting bugs, fill those accordingly
   

1. Click "Next" and your build will be submitted for a review. The review process usually takes about 48 hours, but it can take more. Keep in mind that in case your app is not compliant with the policies and guidelines from Apple they will reject your build and you will need to upload a brand new build before you can submit it for a new review
2. Once your build is approved you will be able to generate a public link, which can then be shared with users that you would like to give access to the app for testing.