I must have expressed myself poorly.

What I mean is:

Why not fork Osmand and then add the functionality to publish reviews on Nostr for the fork?

OSM already allows publishing places for everyone to find later on and saving your favorite places locally with a note.

I have been contributing for the last few years, but adding the option to publish reviews on Nostr would be the cherry on top of what is currently available. 

 Ah I see. What's that built in? Reason I built this was partially to learn some new JS tech for my dev career. But I see what you mean. 

 Mostly Java.

https://github.com/osmandapp/OsmAnd 

 Downloaded, I'll check it out! I had previously pulled data from Overpass to put on the map also. Very useful data there. 7000 odd locations which accepts BTC also which is cool.