[ctz]

Some observations:

- This uses an external service 'scrambls' (https://scrambls.com/) which seems to do per-message symmetric key management. Therefore, the owners of this service can read all your messages.

- The thing which seems to be sent along with the ciphertext is an 'XID' which is sent to scrambls and exchanged for the raw AES message encryption key. There doesn't seem to be any binding to the recipient in this step(?)

- The encryption of messages is AES-CBC with PKCS#5 padding. There is no message integrity, so therefore this provides no confidentiality under CCA2.

In conclusion, this is the sort of thing you should expect from a secure messaging app. (TextSecure excepted.)

[andor]

It's interesting how they know it's happening, but don't seem to understand the consequences.

In the video, they say that "the key and message can only be read by Sally."

Or look at this one, where they even visualize it: http://siliconangle.com/blog/2014/05/03/the-design-behind-ch...

The architecture of the product features a unique web-based exchange of key transfer capabilities to facilitate completely encrypted messaging.