Just purchased a
mini 2 after using an Air and Phantom 3 for some years. Had same problem ie the black screen of death after flying for a few minutes, the app then recovers after several seconds and you can reconnect to drone. Control is never lost and if flying VLOS there should be no real safety issues. Used two different Samsung tablets (8" A and 10" S), with same fault on each, but it did tend to run longer on the S than the A before the black screen appeared.
Clearly a software fault somewhere. I have some sympathy with DJI here as an ex-software engineer before retiring. DJI have a large app running across five Android versions on over 25 phones/tablets, each of which has its own set of other apps etc. installed, so no hope of much in depth testing with this. Obviously easier to test with iOS devices.
In my experience software faults are often coding/specification bugs and with these every time you put the drone into a particular situation that uses the faulty code it will fail. However, this fault seemed random and difficult to reproduce exactly so I thought unlikely to be this type of fault. Another common type of fault relates to the apps interface with the O/S (Android 10 in my case), especially with shared resource management such as memory or processor power. I think that is what is happening here. Cant do anything about the processor so tried the memory, aiming to give as much as possible to the Fly app. (I only had 2G to start with and much of that was lost to Android , Samsungs apps etc. leaving less than 1G.) So, removed ALL unused and unwanted apps and cleared memory from settings, turned caching off in the Fly app. Set into Airplane mode. Shut off all notifications and as much background, automatic stuff as possible. Result, a lot more free memory and the last two full batteries were used for a full 30 minutes flying each, lots of photos, videos etc but with no black screens. Will keep testing but fingers crossed. Worth trying something like this. Otherwise, rather liking the
Mini 2 especially Ocusync so much better than the wi-fi used with the Air.