I feel a little ashamed that I can’t understand this…

Nothin' to be ashamed of, we're all newbies to this at first. I had to learn it too :p

Part 1: How XMPP servers differ from XMPP Clients

Okay, so: Movim and Conversations are both clients that can be used to login to any XMPP account. Those two clients in particular are a little bit more confusing than normal, because they also offer free XMPP accounts on their own XMPP servers (which are independent of the client software).

To try to liken it to something familiar, it'd be like if the Thunderbird email client (which you can login to any email account with) also happened to offer a separate email hosting service too, so you could login to your SomeReallyCoolUsername@thunderbird[.]com from the Thunderbird app.

Or to liken it to how lemmy works, if you're familiar with the Photon front-end, it can access any lemmy account, even your blahaj account, as it's just an independent front-end, it's not actually hosting the lemmy server itself.

Part 2: How it works in practice

So in practice, if you create an XMPP account on Movim's server, you can login into that same account right from your Conversations App too. The same would apply if you'd created an XMPP account on the Conversations server; you could login to it right from the Movim client.

One client can also communicate with any other. Let's say you had a friend using the Conversations client, and you were on the Movim client; you could talk to each other no problem through text, or even call each other 1 on 1 with audio or video.

Part 3: The complication :(

But, bit of extra complication; the Conversations client hasn't yet implemented some of the features Movim is capable of. Specifically, it cannot yet do group audio/video calls or screenshare. So if you're in a chat room with your friends, and everyone is on Movim except for one friend (who's using the conversations client on their phone), if you started a group call, that one friend won't be able to join it.

However ('But' part 2); that limitation would only crop up if someone is using the Conversations client/mobile app itself.

If that same friend happened to have a Conversations XMPP account, they could still open Movim in a browser tab on their PC or phone and login to the Movim client with their Conversations account, and then would be able to join the call no problem.

And that's it! :D

Sorry if I didn't do the best job explaining that. I'm very much looking forward to the day when Conversations gets those missing features and I only need to explain the first part about how clients and XMPP accounts are separate 😅