[gtf21]

Telegram has the same problem with "Secret Chats" which can only be read on the device from which they are initiated.

[izacus]

People don't use Telegram (or whatsapp) for secret chats, but because it's a UX friendly messenger that replaces paid SMS services.

[tazjin]

Yes, but the amount of people who actually use secret chats is tiny.

It reminds me a bit of the CAP-theorem: Security, Device Sync and Usability. Pick two.

My personal preference is solving DU, because I can do security aware stuff with GPG.