Secret Chats are device and session-specific, meaning they don’t appear on a user’s other devices, and will be cancelled if one of the participants logs out.
These chats prevent forwarding messages and have extra privacy features – like a self-destruct timer that erases messages after they are read, as well as screenshot alerts on iOS and screenshot blocking on Android. You can identify Secret Chats from the 🔒 icon in the header and on the chat list.
End-to-end encryption is provided by Telegram’s MTProto 2.0 protocol, which has been independently verified by thousands of researchers.