An end-to-end encrypted app that doesn’t require a phone number

There’s at this point plenty of encrypted, and open-source messengers in the market, who appear to do the job they are meant to do – providing secure and private communication to users.

But when looked at more closely, the job is seemingly never-ending: just how private and secure are any of these apps? There are so many moving parts – and what precisely is their open-source and encryption policy?