Signal coupling always worked for me here ; the key point I think is more the fact that Signal actually is developed with the idea that it is associated to a phone number. They go to impressive extents to demonstrate that they themselves cannot know your phone # while being capable to safely connect it, and that indeed is an impressive achevement.
But your Signal instance is basically related to your phone. You couldn’t have Signal without a phone.
Now, Signal installs in an extremely simple way, it sports a really large range of features (including videoconferencing!), it’s open source and developed by German credible guys… that’s a lot of convincing features!
I am on Signal, and while in the beginning I really only used it for very specific conversations (some important foreign customers, my elected administrator in the large company I work in), I discover that more and more of my correspondents and friends progressively appear to install it. So, there is a small bur real progressive adoption.
Jami, a Canadian open source development, is to me “technically the next convincing step” : to Signal privacy it adds the independence from a central server : not only nobody could “kill” the service by banning the server, but compared to Signal where nobody can know what you say but some can see who you are calling, Jami prevents such a detection by design.
So it is the next step in safety and in privacy.
In addition Jami is not requiring a phone number, indeed you can have a Windows Jami, a Linux Jami, and Android Jami instance, all separate or all sharing the same identity.
I think this is safer and simpler. But for groups that use to call each other primarily on GSMs this shouldn’t count much.
I come to the nasty feature just at the end : installing Jami is a bit more complicated that Signal.
Indeed it’s (only) like facebook & all : you must create an identity, in various steps, which results in a specific ‘signature file’ only present on your machine.
Actually the steps are reasonable (for instance on a phone the said signature file won’t even appear to you if you dont’ look for it, it’s transparent), but probably these steps will look annoying, and maybe more prone to errors in the setting up.
I’m on Jami too, definitely appreciate it, but have really few correspondents.