What makes ChatSecure a better choice? What can I do with it that they can't?
It ChatSecure is an XMPP client; XMPP being an open federated protocol.
Signal uses Google infrastructure; while this isn't an issue for security purposes (because everything is encrypted), some people don't like it, some people like to run their own servers. With a "centralized" protocol like Signal, running your own server means you are cut off from everyone on the main server; with a "federated" protocol like XMPP your server can communicate with the other servers, so you can chat with users on other servers.
The innovation with ChatSecure over other XMPP clients is that it has implemented an XMPP extension (XMPP is an extensible protocol) called "OMEMO" that implements encryption, by borrowing substantially from the Signal protocol. This is an improvement over OTR, the status-quo way of doing encrypted XMPP, which the linked page explains was designed around desktop usage and doesn't work well with phones.
https://copperhead.co/android/docs/usage_guide
Basically ChatSecure is a nice clean XMPP client (turns out XMPP is not actually that scary, and choosing a network is no worse than choosing an e-mail provider), that supports OTR (and now OMEMO, which is much better). For Android, there's conversations.im, which was the first one to really support OMEMO.
Basically means you can choose your client, networks handle the messages, and it's up to the client each person is using to handle the crypto.
DuckDuckGo: Adding people doesn't seem to work via QR code, at all. And the client gets weird when trying to delete the account.
evil.im: Adder never gets notified that they have been "accepted", so can't view the conversation except via notification.
null.pm: Adding works fine, but OMEMO just stays at yellow exclamation marks.
dismail.de (supposedly has a fully green bar): No QR code adding, no notification of accepted contact request, OMEMO is fucked.
talker.to Basically the same as dismail.de.
So is there an actual server that is reliable and supports the requisite features set to make this a usable experience?
Are these client bugs?
Because otherwise this is going nowhere. I'm sitting next to my mate and cannot actually find a server that allows us to communicate normally.
I'm trying to set up a Jabber prosody server and I think it's working. I have no idea how to test if it is really. I got A/A on the server test thing.
How do they compile a list like this?
https://gultsch.de/compliance_ranked.html
Do they have a suite that I can run against my own server?
Most probably yes, you should report such things to the issue tracker at https://github.com/ChatSecure/ChatSecure-iOS
Do they have a suite that I can run against my own server?
The compliance testing is performed by https://github.com/iNPUTmice/ComplianceTester
You should also be able to ask Daniel (iNPUTmice) in the Conversations chart room at https://yax.im/i/#conversations@conference.siacs.eu?join <xmpp:conversations@conference.siacs.eu?join>
