I try to use MapKit, when possible, as it is unencumbered by licensing and support issues (and works pretty well), but I have considered MapBox. It’s commercial, but pretty straightforward, with licensing and support. I have heard good things about it.

I don’t really know about Maplibre (but I’ll check it out).

Had a friend create an app, based on Google Maps (if you remember, in Ye Days of Yore, GM was the mapping engine for iOS), but Google did the licensing rug-pull thing, and he had to do an emergency open-heart surgery to his app.

That was a sobering lesson about relying on third-party dependencies.

[EDIT] Looking at your app, I’ll not be surprised, if you’re familiar with my friend’s app: EasyRoute