I Have only been flying for about a week now.  The app on my phone will stop working one or twice during a flight.  
I am using an android Moto G5 phone.  The phone is only about 6 months old and the operationg system is up to
date.  I have notice it is not on you list of suggested phones.   

If this is a bad choice what tablet would be a better choice.  

Bob

Look at the suggested devices and pic one of those would be your best option.
You will find that many devices will work but theres also a lot that dont

my I pad mini keeps shutting the app off too

Hi Bob, Moto G5 is not on the recommended device list, but you can still try to remove the APP, then install it again, see if it helps.  You can also enable the airplane mode when this APP is running. If it persists, I would recommend you use an recommended device, here is a list for your reference only.

concrete guy Posted at 2017-12-3 08:58
my I pad mini keeps shutting the app off too

Hi, could you please provide more details about your issue for better assistance? Which iPad mini are you using? What iOS version? Have you tried to delete the APP with all related files from your iPad, then install it again? If yes, how is it going?

concrete guy Posted at 2017-12-3 08:58
my I pad mini keeps shutting the app off too

I also experienced the same problem with iPad mini 4.
APP shutting off in the middle of flight.

and now it always happened for approximately in every 1 minute when I open DJI GO 4.

I reinstalled the app and refreshed and upgraded my ipad and its seems fine now

yosephat Posted at 2017-12-4 00:30
I also experienced the same problem with iPad mini 4.
APP shutting off in the middle of flight.

This is exactly what I am experiencing and I am assuming the device is overheating. your thoughts on that.  

djiuser_SMhMUlo Posted at 2017-12-6 07:40
This is exactly what I am experiencing and I am assuming the device is overheating. your thoughts on that.

No, temperature is in normal usage I think and not Extremely hot (iOS 11.1.1).
But now it never happened again when I Update iOS to 11.2.