Bump for Delta Chat. Onboarding is easy as dick, just have them use the default server (nine.testrun.org iirc) unless you have a preference, and pick a uname, don't even need a password. The "invite friends" tab in DC is handy as hell. Modernish feeling chat to boot, and experimental video calling (works pretty fucking well tbh, better for me than Element's calling on Graphene without push notifs actually.)

I do like XMPP but it's still too hard for the normals still unfortunately, no easy "invite friends" that sends them directly to their app store and points them at my acct for me to send, and generally harder onboarding for them. And when I do get someone they complain about the outdated apps. And OMEMO is good but most apps use an outdated implementation and updating it would break compatibility with whoever didn't. I still use it as a fallback, but Delta has so far been what I've been needing.