local webservers on firefox aurora
This looks promising - allows you to create web servers from inside the browser, accessible to the local network! and also uses mdns to discover available services.
That says firefox nightly, but the more up to date site https://flyweb.github.io/
says it works on firefox aurora which you can install via google play. This could potentially mean that websbot could auto detect and do seamless local networking!
Looks like it's intended for opening a page hosted locally in the browser, and then communicating with that server. I wonder if it's possible for a long-running webapp to do local p2p via this? This might be enough to exchange webrtc introductions locally. Wondering if you can open a local webfly page in a iframe or something?