title: iOS Facebook SDK v4: App Invite sends successfully to test users but not others
body: <p>My app is live on the iOS app store and I've set up App Invites with the latest FB SDK (v4).</p>
  
  <p>Everything must be set up correctly in terms of the App Link as the invite works with test users but not non-test users, a notification is received and the user is taken to the app store when they click on this.</p>
  
  <p>Is there an extra setting on the Facebook side that needs switching on for this to work with regular users?</p>