I use OSMand more for car navigation or hiking navigation, CoMaps for me is more for finding out about a store, or a coffeeplace in the city somewhere... the search is somehow just miles ahead of OSMand (which almost never satisfies me) and the UI decisions just seem better for that. It also looks fantastic, although OSMand is highly customizable and for car navigation i'm really happy with the map settings i have.

It's a very different approach. Personally, I could never fit OSMand into my daily routine, but this one has been great.

It's not a reskin, it's built from the ground up. Although it is technically a fork of a fork (not OSMand).

For me, much more user-friendly and intuitive and even quicker. They both use open street maps data, but I think they are worlds apart. I haven't done any testing with OSMand for a couple years, so I couldn't tell you which specific features are different.

I find it very easy to read, day or night. It's quick to add a destination for navigation. It's very easy to create updates directly from the app that will upload to OSM.

Osmand~ and CoMaps (fork of Organic Maps) use the same map data, but different rendering/routing engines.

Osmand~ is everything and the kitchen sink. Any feature you can think of, it probably has

CoMaps is just the basics for 85% of people. It's much simpler, its map drawing is much faster (no lag while waiting for tiles/branches/labels like Osmand), and much faster on-device routing than Osmand.