“OMEMO is broken in general across the ecosystem :(”
“In a nutshell, if you are testing OMEMO compatibility across the ecosystem with different clients and platforms, don’t do it. It’s a waste of time until this is resolved by every client.”
Coming from the developer of one of the most actively maintained, source-available XMPP clients for iOS, Monal.
Personal instance of nitrohorse (nitrohorse.com).