I want to calibrate the compass of an android tablet, I know I can do it by doing the "8' figure, but, I want to do a calibration without moving it because my tablet is fixed and can't be moved. Is there any method to simply add or remove some degrees to the compass offset?.. in other words, if my compass shows that my heading is 260 degrees and I know is 300, can I add 40 degrees to adjust it?
I havey device rooted but on the last android versions the filesystem is not writable, is readonly. With Magisk I can write some script to update many files.. Or maybe there is a simple app to do that.
Thanks