monitor - tablet - ipad

Sorry if someone has written this thread before but I got tired of looking. So I bought the controller without the built-in screen. Between it being hard to see the phone screen and it occasionally falling out of cradle, I regret that choice. So gurus, what is a inexpensive tablet that will do...

I have a Samsung 6 and use it with my Phantom 3 Pro, the screen works good, just wondering if what other devises are being used?