I case you have a non-cellular iPad or mini-iPad (which don't have GPS), and you wish it did have GPS (use for dynamic homepoint, ground station etc), here is a fantastic little GPS receiver, which connects to your iPad with Bluetooth. It gives your non-GPS iPad full GPS capability, just the same, or better, than the GPS-equipped iPads.
http://gps.dualav.com/explore-by-product/xgps150a/
I have two: one for flying, and one on my boat. They work great!
http://gps.dualav.com/explore-by-product/xgps150a/
I have two: one for flying, and one on my boat. They work great!