Comment by DarkUranium

IRCv3 gives you all of that, and I'm working on an ircd that has builtin support for multi-device access & chat history (which covers mobile between the two --- there are improvements you can do on top of that, but those two are kind of the foundation).

I'm also extending it with support for Discord/Matrix/etc-esque communities (in a 100% standard-client-compatible way).