TestFlight Questions for Freemium App

Beginner here. I'm looking to deploy my app on TestFlight and have a few questions:

  1. My app has a messaging feature that connects 2 users in-app to chat: is that possible in TestFlight to send a pairing code to connect 2 devices in the app?
  2. Can users pay for to unlock premium features? If build only lasts 90 days, what happens if a user pays to unlock premium for a whole year?
  3. If so, what happens to the premium account once we launch in app store?

Thanks!

TestFlight Questions for Freemium App
 
 
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