I imagine certain features like Google Maps’ different busyness indicators might be missing because otherwise that would require telemetry?
Try OrganicMaps (https://organicmaps.app) on Android. It’s awesome!
Only thing I consistently don’t see well done are parks and other green spaces, where the boundaries are ill defined or missing. Other than that, also my mainstay
Try adjusting them on openstreetmap.org/edit, takes a few minutes at most
The FOSS ones suck in comparison honestly. There’s really just osmAnd that has a really ancient UI. As for other OSM(OpenStreetMaps), I find MAPS.ME to be the best, but it’s closed source with some crypto scam crap built in that you can’t disable.
I don’t really like OSM based maps because they miss tons of places where I’m at, when I specifically need building numbers and locations. Also the search on both apps is god awful and straight broken.
Google Maps is definitely miles ahead of the competition here. The other features like seeing how busy businesses are, reviews/images, menu and phone number/website. These are also icing on top of the cake that make it essential to have which none of the competition have, let alone any FOSS ones.
Honestly, OsmAnd doesn’t have that bad of an ui these days. I’m perfectly happy with it, most of the time. Definitely prefer it to Google Maps while cycling.