I have found the compass bearing to be complete inaccurate when flying my p3 in the outback/country when flying with my ipad mini2 wifi only yet it works perfectly with my ipad mini 2 cellular (built in gps). Does anyone else use the compass bearing and notice it is incorrect at times?

I cant get mine to calibrate - even straight out of the box - any ideas?  I even looked at the compass sensor value and its floating at about 1000 instead of the 1500, and apparently it doesnt matter whare i go in 500 acres or the beach there is always electormagnetic interference - maybe you could look at your sensor reading value  when youve got each respective device in use to see if its reading differently. then go from there.