If the app crashes or disappears, the drone can still be controlled using the sticks and visual control (that is if you can see it). In my case, I just touched the DJI icon and it started right back up. I suppose if it's beyond sight, and you can't get the app back up such as in the case of the phone battery dying, then using the return to home button on the controller would be the next thing to do. All my firmware versions were up to date.Sounds very scary. Fortunately, I haven't experienced any software issues with this tablet so far, hope I won't.
How did the drone responded to app crash? Have you checked if there were any pending OS or App updates?
This weekend I took my first real flight with my Hauwei MediaPad M5, 10.8". Several times the DJI Go4 app seemed to crash while flying the Mavic Air. ...or at least the app disappeared, requiring me to restart it using the icon, so I'm assuming that was a crash. I was using the DJI USB-C to USB-A cable to connect to the controller.
I switched back to using my iPhone 6S plus and finished my flying with that. Never had a problem with the iPhone.
Anybody else experience something like this with this tablet?