[orblivion]

> And it has a barrier to entry - you have to be a tiny bit nerdy to confidently make edits.

https://wiki.openstreetmap.org/wiki/StreetComplete

Highly recommended for on-the-fly edits. It's available on F-Droid too. The most complicated part of it is entering your OSM account credentials (and perhaps the fact that you have to tell it to Upload changes; early versions didn't even require that). From there on, you just wander around town and you click on POIs and roads that pop up, and it asks you to fill in very specific bits of missing information. What are the opening hours of this place? What's the address of this house? What kind of roof does this house have? What style of road is this? What's the speed limit? Etc. It's got pretty icons and helpful images for what you're labeling (different types of road, different types of roofs, etc), and no confusing frills.

I had the idea for exactly this sort of thing myself for a while. Thankfully somebody did the work for me.

[Cyphase]

I had a similar idea a few years back; an optionally-always-on mapping app that made it really easy to add data and fix existing data, with prompts about nearby things as you're moving around.

Yet another example of how execution is what matters, not the idea.