I've always wondered if something like this could make and join a mesh network, so communications could be over relatively longer distances.

From what I recall, @derwildemomo (OP) has experimented with this, but the current smartphone stacks are a bit fragile for that kind of workload. I'm sure he can go a bit more into detail once it's not in the middle of the night in Germany :)

A question I have after reading this: does it work Android to Android with no iOS device around?

Hi, author here.

No. Not using Bluetooth LE, since there is no support for acting as a "server" device that can be discovered by other peers. It's sure to come someday, but right now it's only possible using a rooted phone.

It maybe possible that Firechat uses either Wifi Direct, which is supported on most modern Androids or classic Bluetooth, although the discovery/connection requires user interaction.

thanks derwildemomo, what you're saying makes sense.