DJI/Ryze (or some other developer) needs to develop an FPV app for the Tello. Why should Android users have all the fun??? I also think it wouldn’t be that difficult to add FPV to the standard Tello app by Ryze.
I don't think you'll have much luck asking Ryze to add such functionality to their app. They could have added RTH from the beginning.
I am currently finalizing my first IOS app. It will give some fun to IOS users that Android users don't have, so we are back to a draw. Well, at least I hope so.
After that I'll look into a rebuild of TelloFpv for IOS. But that will take time...