I wouldn't trust it. You're probably better off using a libre program like Mumble for chatting.
I don't know much about this service (mostly on account of the FAQ not being
complete), but it looks to be nonfree and is definitely saass.
- [Trisquel-users] cyph encrypted softphone is saass? svhaab
- Re: [Trisquel-users] cyph encrypted softphone is saass? travis