Hello, newbie here so go easy on me. I've had a Phantom3 Adv since Christmas and have used my iPhone, but I've complained that the screen is too small so today I got a a 7" Fire tablet. So, will I be able to use this if I dont have cell/mobile service? If so, what if I am somewhere where I cant get wifi, which is pretty much everywhere that I fly? My daughter syas I need to connect the Fire tablet to my cell phone as a hotspot. Any advice and info much appreciated.

You do not need wifi to fly...    Unless you cache the google maps,  you will just not have them when you fly w/o wifi.   Also, the follow me function will not work.   Everything else will work fine.  That being said,  I am not aware that a Fire tablet will work with the DJI Go app.   
http://www.phantomhelp.com/tips/18/best-tabletsphones-for-dji-go