

XMPP, but also Delta Chat! The Webxdc apps for Delta work in XMPP client Cheogram despite there being no cross-compatibility between the networks. It can access ordinary email servers so long as they were not set up maliciously (Apple, M$, Gmail, etc). It can do a couple things XMPP cannot, but it’s not suitable for anyone outside close friends and family. I basically only use it for email, automation, and other personal matters. XMPP is for general use and can replace Discord. The Movim project looks very cool they have a community here also join their XMPP chat. Cheogram services can connect to the regular phone network.
PostmarketOS makes no claim that it is ready to be a daily driver, Linux phones are pretty experimental right now. That’s why there is so much tension over the custom ROMs that manage to function on such locked-down hardware