Yeah, I love OSMAnd for that reason. With it, you can add POIs and for more complicated edits that need a bigger screen etc. it's easy to add OSM Notes (which other mappers can then follow up on). Notes I find particularly good when I'm travelling and don't have time or enough knowledge of the area to actually edit the map, but want to help others do so.

Go Map! is indeed a fine app. But it does require some OSM knowledge, like the various tags. In that regard the linked Android app is a lot simpler.