guardianproject
Needs built-in mechanism for syncing keys with other clients
There needs to be a built-in mechanism for syncing keys with other clients, for instance, the desktop client Pidgin. UI should be crafted such that it is automatic and fool-proof to configure messaging to work across multiple clients, otherwise this will struggle to gain mainstream appeal by non-tech-savvy users.
We do have a system called KeySync that allows this: https://guardianproject.info/apps/keysync/
though we are currently fixing some bugs in the desktop apps.
I see. I actually tried that and it didn't work, but assuming it did, do you really think it's reasonable for it to be a different app?
I don't think most users would understand/expect that they had to go somewhere else to sync keys. I think a better design principle would be to presume that the user doesn't even know what a key is, and use language that doesn't mention keys (or any technical details) to sync 2 clients. If my girlfriend or my mum didn't have me to configure for them, they'd never get there. Mainstream adoption depends on framing it in terms that most people can understand. It probably needs to be a button visible in the same place as sending messages, otherwise I think most users wouldn't even imagine that it's possible to 'sync keys'. They'll just assume that what they get is what they get.
If you just want to sync you keys between ChatSecure on different phones, we can do that quite easily. Since Pidgin is a desktop app that we don't implement, our solution was to build KeySync, which, while still rough, makes it possible to convert keystore formats between many different desktop chat apps and put them into ChatSecure format.
Overall, yes, it needs to be asy for mainstream users, but I think most mainstream users will likely just a messaging app on their primary smartphone, and not have multiple devices, etc.