[Vinnl]

There's this, by a respected cryptographer who, however, also is the author of Signal: https://moxie.org/blog/telegram-crypto-challenge/

[miaklesp]

Any less biased source?

[45h34jh53k4j]

Moxie might have his own horse in the race, but his analysis of cryptosystems should not be questioned. His philosophy is around humans being able to access strong encryption. I believe he ultimately doesn't care what you use, as long as your communications are secure.

[Vinnl]

And to illustrate that, he worked with Facebook to add Signal's encryption to WhatsApp (and Google to Allo).