Is there a link to this I can’t find?

All the documentation is really scattered (partially due to the interwoven nature of having a stack of different protocols/services).

necessary for outbound telephone calls (to landline/mobile phone network)?

… or, put another way:

  • are there any XMPP clients one is aware of which can NOT do so?

More generally, Is there a list of What XMPP extensions are used by JMPchat (and for which purposes)?

  • singpolymaM
    1·
    18 hours ago

    Any client that can do voice calls will work with JMP.chat. As a user generally it’s not useful to think about XMPP or protocol extensions, this is an implementation detail if you’re building a library or SDK. We consider Cheogram Android to be a first-party app and all Snikket branded apps to be pretty close, everything else is a third-party app with the uncertainty that entails, but basic functions like text messages and calls are standard enough to pretty much always work.