It's always on until you lose the signal.
I always fly with a Trackimo GPS tracker. You can find all of the other commonly used trackers here:
DJI Phantom Accessories & Tips - Phantom Help
See the following thread for retrieving flight data:
DJI Forum|Phantom 3's Flight Recorder
No, and it takes a while to load.Just says map loading. Do I need the Sd card in the tablet?
Could be be a cable?How about screen lag? Galaxy 4 tab on airplane mode.