Anybody ever have any issues with the magnets in iPad cases interfering with the iPad's compass? I'm currently test driving/debating between an iPad mini w/Retina and an iPad Air. I have each device in a faux-leather Snugg case. I've also installed SkySafari Plus (an excellent astronomy app) on each device. With SkySafari Plus there is a "compass" mode that allows one to hold the iPad up to the sky and observe on the iPad screen the stars, planets, etc., in that direction. SkySafari's compass-mode has been working fine with the iPad mini/Snugg combo. For example, whenever I point the iPad mini to the western horizon when in this mode, I always see the western horizon properly centered in the screen. It's a different story with the iPad Air/Snugg combo, though. With this device/case, I often get a request to recalibrate the iPad's compass (roll the red ball around the circle) when (or soon after) I enter SkySafari compass-mode. And when asked to do this, the recalibration screen disappears before I can finish "rolling the ball." Then, when I point the iPad Air to the western horizon, the screen centers on, maybe, the southwestern horizon -- a good 45 degrees off. After playing around a bit, I seem to get correct performance with the iPad Air when its not in its case or, when using the Snugg case, with the Snugg case flap held perpendicular to the back of the iPad Air, i.e., with the flap is not lying flat on the back of the iPad Air. I assume that this is an issue with the Snugg case for the iPad Air and the strength of and/or relative location of its magnets with respect to the innards of the iPad Air. Or is it possible that the compass hardware/software of my particular iPad Air is a bit gimpy? (I guess I can have Apple swap my iPad Air for a fresh one and then check SkySafari compass-mode performance with the new device in the Snugg case.) Anyway, anybody ever experience compass issues with certain iPad cases or covers?