Preferably Android apps available through F-Droid, but feel free to recommend iOS apps, too!
On iOS, I really like Sky Guide—I don’t think it’s open source, but it has the right features for the casual star gazer like myself, specifically the ability to point my phone at an object (i.e., “what’s that object up there”) and/or search by name (“where’s Jupiter right now”). After my transition to Android, I’ve found Sky Map, which has good feature parity with Sky Guide.
Any other open source apps like Sky Map that I haven’t found yet?
You might want to look at obtainium as a package source as well
Where would I find the Android releases of Stellarium to do so? Their github only hosts Linux, Windows and MacOS releases.
Looks to me like Stellarium mobile is closed source because they want to monetarize Stellarium mobile +.