ARKit has a big problem in that if "Compass Calibration" is disabled in user settings, GravityAndHeading breaks, and there's no way to guide a user to turning it back on.
Further, it seems that for whatever reason, iPhone X's running iOS 12 have this turned off by default.
Is it possible to openUrl: Privacy > Location Services > System Services > Compass Calibration
Are there any other options available?
