Hmmm, now it seems to be pointing 10 or 15 degrees west of actual north… so apparently it’s unrelated to true-vs-magnetic north issues.
I don’t know anything about how compass headings are read in an iPhone, but I note that two other compass apps (the Apple Compass and the compass in “Bubble Level”) are pointing towards an accurate north. It’s just Stellarium that seems to be significantly off… any thoughts? Thanks.
Mmmkay, by doing the “slow roll around” technique I’m able to straighten it out pretty well. Weird that it’s more finicky than the other compass apps, but maybe it has to do with the fact that it’s often used vertically.