Itâs time consuming, but itâs fun too. Itâs my main hobby now.
The group system is mainly interesting from an engineering and illustrative PoV. Signal is actively working on getting rid of current privacy violations, while I generally find that Threema and others donât spend this engineering effort. This is not limited to groups, thatâs why I also mention unidentified delivery, and their other 40 blog posts that illustrate their efforts. That said, any libsignal
-based messenger is probably an upgrade over SMS in some regard. Maybe the main exception being WhatsApp, but we still have to find out why exactly itâs terribly bad.
Re Swiss-vs-US, you make a valid point if Iâm allowed to interpret your statement very broadly. Signal uses the principle of âtrust on first useâ. A US-hosted machine could actively intercept the first communication, which allows them to be a middle man. If they donât intercept the full line of communication, this will be detected. This is however a MITM attack, and not per se an attack on the server. If you use Threema to communicate with someone US-based, this attack also happens. TL;DR: you donât need a back-door to bypass e2e.
The only way to make sure, and this is a general thing for any messaging system ever, is that you need to check your âfingerprintâ of the derived key, or manually check and confirm the public key of the other party. TOFU is best-effort, and sadly will always be best-effort.
I agree that recaptcha is totally creepy and Googly, but I also see the need of Signal to implement such a system. My hope is that they add more options to verify that youâre a human being; currently they only have reCAPTCHA and GCM, both being Googly.
TL;DR for the full post: I think Signal is moving in the right general direction, while the other competitors feel like a fad or a grab for power, staying where they started. Please do inform me if I tell lies about Threema et al., Iâd be very interested in being proven wrong.