Test of Magnet Case on Compasses

[LTCSZ]

I think it has been pretty well established that magnetic cases/covers will not harm iPads. Everyone from Forum members to Apple has stated this. OK, that's that.
But, do magnets effect apps that are running on an iPad? Particularly compasses and other directional apps. I could not find a definitive answer, so I conducted my own, non-scientific, non-binding and non-provable test. Here is what happened:
1. Went out into the middle of a baseball field (second base) where there were no metal structures, etc.
2. Verified "North" using two standard hiking type compasses.
3. Fired up the iPad Air 2 and tested three compass apps in the naked iPad after synchronizing the compass.
4. All three were within 2 degrees of the standard type compasses. North does not move!
5. Placed the iPad into a case with magnetic closure. and synchronized again.
6. Here's where it gets interesting. With the case cover hanging down, the compasses were slightly off by about three-five degrees. When I folded the case cover into the "reading" position (flat against the back of the iPad) the readings went to around 30 degrees off! Synchronizing did no good.
7. So, my unscientific study shows that if you are going to use a magnetic-close type case with iPad compass apps for navigation, and assuming you do not want to get lost, take it out of the case and synchronize it before use.

 

[twerppoet]

Thanks. It never occurred to be to test this. It's probably why Star Walk's auto point works so poorly on the iPad (but fine on my iPhone). Next time I try it I'll take off the case.

Of course, once you start moving, the GPS tends to override the compass and give you the true heading again. At least it does in most maps apps. I've never tested it with a compass app.

Note: The GPS can infer your heading by changes in position. You have to be moving, and at a reasonable walking pace for this to be reliable.

 

[LTCSZ]

I do intend to try a similar test with the GPS function, but I suspect the magnets will have little or no effect on that. (Was going to do it at the same time as the other test but it started raining!) I have found the GPS to be un-effected by much of anything as long as there is a reasonable good sky view.