[messaging] Briar is in public beta

[Yui Hirasawa]

> Briar is a messaging app designed for activists,
> journalists, and anyone else who needs a safe, easy and
> robust way to communicate.  You can download it from Google
> Play:

And why should anyone believe in your promises of safety if
it's not free software. The fact that you can only install it
from google play seems also be at odds with the target
audience.