253
Is Telegram really an encrypted messaging app?
(blog.cryptographyengineering.com)
This is a most excellent place for technology news and articles.
Signal does this by having your data be unencrypted at rest on your device, and I think that's a reasonable tradeoff because it protects the most import part: data in transit. Or you can be like Matrix and require/strongly encourage setting up multiple clients so you always have a fallback (e.g. desktop and phone). There are reasonable technical solutions to the problem of making an E2EE chat system.