I’ve been using PolarAligner Pro (Astro Tool) for a couple months now. It’s basically an app that helps you align your equatorial mount for stargazing and astrophotography. Pretty solid if you’re into that kind of thing.
Here’s what you do: there’s a compass to point your mount north, and a spirit level to get it perfectly level. And it’s got a few other basic tools too, like a sun/moon calculator. Took me a while to figure out how to use it properly, but it’s actually pretty useful once you get the hang of it.
Look, if you’re into astrophotography or just casual stargazing, you’ll probably like this app. It’s not perfect – the compass and level can be a bit finicky if your phone doesn’t have the right sensors. But overall it does the job and it’s free, so it’s worth checking out.