I think the thought is that the encryption would be in the transport layer, and would have to be unwrapped to cross between platforms. Whereas I think this cou

I think the thought is that the encryption would be in the transport layer, and would have to be unwrapped to cross between platforms. Whereas I think this could be effectively implemented in an agreed encryption of the message itself. However, this risks oversimplifying because the next concern would be the metadata. Who is the sender / recipient? How much data is provided about these actors, phone number, email etc? Is this encrypted?