Hello @Kim Strasser ,
You don’t usually need to create a second app just to continue testing after launch.
After your app goes live in the App Store, you can keep uploading new builds to TestFlight without affecting what users see in production. TestFlight and the production App Store operate on separate channels.
For Google Play Console, you work with different release tracks (internal testing, closed testing, open testing, and production). Once you publish to production, you can still push new builds to any of the testing tracks. Testers receive the test versions, while regular users get the production version.
You can check out Apple’s TestFlight documentation and Google Play’s release management guide for more details on how these workflows operate.
While these are not Microsoft websites, they provide official guidance on the respective platforms.
I hope this clarifies, and happy holidays.