The Nividia Shield has proven to be a great android workhorse of a tablet, but, they are around 200 + .
I;ve used the shield since day 1 for my P3A without any issues.
Partnered with my Mavic pro I have the Acer Iconia one, which also works with no lag, no dropouts, no problems at all. The Acer I bought at Canada Computers for 90 odd dollars, refurbished units are anywhere from 65 to 88 dollars. It seems , you have to get the Acer iconia with the MedTek processor I think its # 770-or 780,
I can post the exact model # for you or go over to Mavic posts & look up "Android tablets that work with the DJI go 4 apps".
Couple weeks ago, I'd left the shield at home & did hook up the Acer to the Phantom, I flew a waypoint mission using the Litchi app, 3 -4 flights with no issues at all.