Signal is the world’s most widely used truly private messaging app, and our cryptographic technologies provide extra layers of privacy beyond the Signal app itself. Since launching in 2013, the Signal Protocol—our end-to-end encryption technology—has become the de facto standard for private commu...
As I wrote elsewhere in this thread, XMPP would be my preference. It just works. In fact that’s what the other messengers (at facebook, Google, …) already use, but chose to put behind a walled-garden.
What matters is that whatever comes next (or, from the past in the case of XMPP) is federated, so no single organization has a single-handed control/monopoly over the network. Matrix and SimpleX are federated alternatives to XMPP, but I don’t see Matrix stabilizing any time soon, and SimpleX just isn’t ready yet. XMPP can offer you today an experience that’s comparable to WhatsApp/Signal/Telegram/…
My only problem with XMPP (and a lot of other federated protocols) is really the lack of quality clients. Most of them (especially on systems beyond Android and Linux) don’t really have that good of a UX, or their UI is kind of bland or dated.
It’s something that I hope gets improved eventually. Because having a variety of choices doesn’t mean much if none of the choices feel particularly good.
Want a modern android XMPP client? Try monocles chat. Its UI is kind of modern.
I got mom to use Conversations.
What’s up with monocles dev? They have a bunch of forked projects with their own name.
Monocles Launcher is based on KISS Launcher.
mail is based on K-9 Mail
What the other responders said (there are great clients out there, that fit mainstream and niche needs).
Also, it is not a problem of “federated protocols” per se, but of community-led projects. On the downside it may lack consistence and direction, but on the upside you can step in and contribute feedback, tests, documentation, and why not, code :)