say that you left your Location turned on and held your phone upside down. If you want to fix that, try this:
strip: ffmpeg -map_metadata -1 -i input.mov -vcodec copy -acodec copy output.mov via http://askubuntu.com/questions/139570/how-do-i-remove-all-metadata-from-a-quicktime-movie-file (read comments)
flip: ffmpeg -i in.mov -vf "vflip" out.mov via http://superuser.com/questions/578321/how-to-flip-a-video-180-vertical-upside-down-with-ffmpeg (then to ffmpeg documentation)