@Wrewdison One of the things that I’d like to see in this kind of system is a solid ability to control the precision at which you share location. To me, any system you’re going to advertize as being private or secure needs a fairly robust way to do this.
I’ve been looking at https://h3geo.org as an approach. It’s a hex grid that supports 15 resolutions from ~1,200km accuracy to ~0.5m in a 64 bit binary representation.
The library is in C, but I haven’t looked at how suitable it is to run on an embedded device.
I’m currently in the middle of an international move, and most of my hardware is on a ship somewhere in the middle of the Atlantic, but once I get settled I’d be interested in giving it a try