My oldest son messaged me yesterday with a single link: https://arcanechat.me/ This led me down a rabbit hole that is absolutely revolutionary. Here's my best understanding of how this technology works. Take email, layer on some crypto, have it only work with encrypted messages, remove the idea that the server retains data for any substantial period of time, and you get pretty close to something like Nostr, except without all the cryptocurrency stuff layered on, and it uses an existing protocol (email) rather than a new protocol. This is https://mailchat.at. The relay model is extremely powerful. We currently live in a world where people talk about *hosting*, and we know services like Facebook, Instagram, and Youtube are fundamentally accepting, storing, and serving that content, whatever it may be. This often leads to discussion of responsibility and blame when the content is undesireable to some, and often leads to requests that the hosting company remove the content. The relay model sidesteps this entirely: it's a service that routes data, nothing more. That means there is no content to take down. If the content is showing up somewhere, it's because an agent (human or computer) decided to send it. This keeps the relay dead simple and cheap to run. Once you have a relay, you can route messages to others. While folks typically think of those being chat messages, you could allow folks to pass files to one another that are built with web tech, but are not allowed to access the internet. They instead use a JS messaging shim that routes everything over the relay. Each file can be thought of as an app, and each app might have its own message types that don't necessarily show up in the chat, but are routed to the same copy of the file other users are running as a sandboxed "app" on their device, with all the communications routed via the relay. If you used this approach, you would have recreated WebXDC: https://webxdc.org/ And that's what Arcane Chat and Delta Chat are: webxdc platforms where you make groups with friends, and run apps: grocery lists, card games, arcade games, even minature social networks that all live inside of the chat app. The amazing part about this is that, just like the relay, there is no app store - apps are just files users pass around. State is computed on each client separately by each app - either using CRDT or a more basic synchronization mechanism (with leaderboards, for example, you can just send a message every time a user beats the game with their score, and those can be replayed by the app to compute the leaders).