I found out something...sort of by trail and error. If using a Gamesir controller you can actually leave the Tello app. and use your phone, say to take a photo and continue to fly your Tello with the Gamesir controller, doing various stuff and of course LANDING if need be. I have found the command (R2-Y) on the Gamesir actually very nice...almost a no-look option if you suddenly need to get the Tello down. Landing or at least starting to is a great controller. The photo is a self portrait taken with my 'controller' phone, while experimenting with a small camera on top.

