Looks interesting. Have you tested it?
Discussion
Yes & it sucks it's been in the same state over a year now.
Why it sucks?
Tried it a year ago it's super alpha & pretty broken. Looked at it again a few days ago still pretty much in the same state it was last year not a single new feature has been added.
This however is productive & rolling out updates constantly improving & listening to the people.
https://simplex.chat read the protocol in the docs.

