I'm on a smartphone. But OTR expects the opposite side to respond immediately. So not SMS or anything of that sort. The signal protocol for example was designed

I'm on a smartphone. But OTR expects the opposite side to respond immediately. So not SMS or anything of that sort. The signal protocol for example was designed to work around that. A client can be offline when you send a message. Different protocol design that involves stuff server side. > Not even if it were only available open-source? No. Very few people can assess if something is cryptographically sane, and a lot of people need to do it for something to be believed secure. I'm not one of those people. I'd rather use state of the art crypto. Thanks.