I also recommend SC Expanded and Extended if you have experience with StreetComplete. It adds direct editing functionality and more quests.

Or Reticulum Network via RNode (/its firmware)

Sounds like it’s straight from the good ol’ internet days^TM

Yeah, I was very excited after I heard they could run basically anything you put on the internal SD. It’s hardware ‘made’ for Linux without the extra price bc nobody outside the tech bubble cares.