You will probably need at least Message Carbons (XEP-0280)[0] to synchronise your devices and maybe Message Archives (XEP-0313)[1] to have some kind of history

You will probably need at least Message Carbons (XEP-0280)[0] to synchronise your devices and maybe Message Archives (XEP-0313)[1] to have some kind of history available to them. However this not really tied to OMEMO itself, it's just to provide what's expected of a modern IM experience. I think all servers support them nowadays, anyway. [0] https://xmpp.org/extensions/xep-0280.html https://xmpp.org/extensions/xep-0280.html [1] https://xmpp.org/extensions/xep-0313.html https://xmpp.org/extensions/xep-0313.html