Like todd said an existing library exists, this is the site for the spec https://webxdc.org
The gist is that you get no internet / threading whatsoever, but you get additional API's to get someone's username for example. Then you also get an API for a realtime channel with the other people in the chat who have the app open.
With that you can do a lot, so people can send chess data over the realtime, submit match replays to chat, even do it slow turn based over chat, etc.
One of the most advanced ones is a fully functional runescape server and client. You open the app, it loads the character progress from the chat and if nobody is hosting yet it begins to automatically host the world for the others.
:H::e::n::k::y:!!
npub160…x889v
2026-10-16 16:53:40 UTC
in reply to nevent1q…7t7m
Author Public Key
npub1600yr4qg5vcfp7svf6ysj0008tn7aphnu0gjs6lw5hjn74n0laasjx889vPublished at
2026-10-16 16:53:40 UTCEvent JSON
{
"id": "2d9041759103a0bbdd4ab37050f5b8cabd83e1f1a6107857a7418d45e558c633",
"pubkey": "d3de41d408a33090fa0c4e89093def3ae7ee86f3e3d1286beea5e53f566fff7b",
"created_at": 1792169620,
"kind": 1,
"tags": [
[
"e",
"21d8e7f3ed60d50395a10923301f64343c1d52f1166397f63206c192e5fb96ca",
"",
"root"
],
[
"p",
"c7fe92f80c516c0c54b15e8d256ac07281036d934ea1ff39fb0cd8a0fd677736"
],
[
"client",
"mixstr.pages.dev"
]
],
"content": "Like todd said an existing library exists, this is the site for the spec https://webxdc.org\n\nThe gist is that you get no internet / threading whatsoever, but you get additional API's to get someone's username for example. Then you also get an API for a realtime channel with the other people in the chat who have the app open.\n\nWith that you can do a lot, so people can send chess data over the realtime, submit match replays to chat, even do it slow turn based over chat, etc.\n\nOne of the most advanced ones is a fully functional runescape server and client. You open the app, it loads the character progress from the chat and if nobody is hosting yet it begins to automatically host the world for the others.",
"sig": "b8317f900302e8dce0c8e5269e3bee72afeb7d5bbfa0f3cebd324d05ea85742257b79aa24e711d43207365bcf78207b412c67b29d67cc3cc8345dbd0029ee242"
}