Feature Request: Synchronize calendars, contacts and tasks between devices

[renne]

I suggest to synchronize calendars, contacts and tasks between devices (e.g. Android, IOs) and Signal-Desktop to avoid the need of third party servers. Signal-Desktop can emulate a CalDAV/CardDAV server on the loopback device for local applications.

[chiraag-nataraj]

That sounds like a terrible idea tbh. Signal should stick to one thing and one thing only: secure messaging. Doing more than that means more complex code, more opportunities for bugs, and more opportunities for things to break in a non-trivial way. What you are asking for is a general-purpose sync for things that have nothing to do with messaging.

[renne]

On one hand it increases code complexity, of course. On the other hand users can get rid of data krakens like GMail and iCloud for synchronizing very personal data. In my opinion the Signal protocol is very suitable here and the Signal-App developers have the necessary experience in cryptography. You should also consider the social component. Especially in cryptography users have trust issues with new apps/vendors and stay where they are if there is not much more trust with the new application. The Signal app doesn't have that problem.

[chiraag-nataraj]

I think it would be useful to have a separate app which would sync this (as well as other arbitrary data maybe?). Maybe even sit down and develop a protocol for this that is optimized for this specific situation (there's no reason the Signal protocol is inherently optimized for this situation, and there is a very real chance that transferring stuff like this requires a different threat model and therefore a different algorithm from the current use-case of the Signal protocol).

Like, if you're suggesting the Signal folks sit down and write a new app that deals specifically with this problem, I'm on board with that - the more solutions the better, imo. But I really think it's a mistake to push this to be inside the Signal app - I'm not opposed to the idea of having a decentralized syncing program (a la Syncthing?).

Signal is great for messaging and we should continue to focus on that specific aim for the Signal app. If there are other apps for syncing personal information (like contacts, tasks, calendars, etc), then that's fine (since they would also be developed by the same folks, you'd still have the vendor trust).