I use OSMAnd~ for navigation, and the "expert" version of StreetComplete for surveying.

I am a happy user of Organic Maps:

https://f-droid.org/packages/app.organicmaps/

https://fosstodon.org/@organicmaps

I mostly use Organic Maps for navigating and sometimes for editing stuff on-the-go.

Organic Maps + StreetComplete to get that quick fix

I've used organic maps with some success

The official OSM wiki has a nice chart with android apps: https://wiki.openstreetmap.org/wiki/Android#Navigation (There are also non navigation apps somewhere else on that site)

As someone else already said Magic Earth is great as a direct google maps alternative, I use it in combination with organic maps which I find better when on foot or looking around on the map.

Been using Magic Earth since its included within /e/OS on my phone. It's been fine for the most part. Sometimes it doesn't recognize the actual address but will get me at least on the street and from there can navigate myself

I like OSMAnd for it's ability to work for almost any purpose you need it to serve. Besides that I enjoy Magic Earth (on Play store) as a Google Map alternative as it's UI is the cleanest.

Vespucci is great for editing.

It's pretty advanced though so maybe not for a casual user.