Don't forget that Signal is the name of the app, and "Signal Protocol" is the name of the E2EE protocol. The parent was talking about the Signal Protocol. The

Don't forget that Signal is the name of the app, and "Signal Protocol" is the name of the E2EE protocol. The parent was talking about the Signal Protocol. The fact that Facebook, WhatsApp, etc. use the Signal Protocol kind of shows that it is an accepted standard. But of course there are many reasons to use Signal (the App) instead of those apps, for instance: - The Signal App is open source. You can check the protocol implementation before you use it. For Facebook, WhatsApp and Skype, you have to trust them (or some audits). - E2EE is only one part: it ensures that nobody except the recipient can read the content of your messages. But there is a whole story around the metadata. The metadata say who writes to whom, and when. It essentially helps build a social graph. Facebook is very interested in this social graph. It would appear that the Signal Foundation is not. And even if it is not perfect, Signal does a lot to try to minimize the amount of metadata it has access to (and quite obviously Facebook has a huge incentive not to do that). This said, IMHO it is still a lot better to use WhatsApp than to use Telegram, because at least you benefit from a good E2EE.