Facebook Messenger turns on promised end-to-end chat encryption

Facebook on Tuesday launched end-to-end encryption for all users of its Messenger mobile app, though the option isn’t on by default, and comes with some other limitations.

“Secret Conversations” must not only be toggled on in the app’s Settings, but manually enabled for each new conversation by tapping “Secret” in the top right corner of the “New Message” screen. Encryption can’t be applied retroactively, and both the sender and the receiver must have the latest version of Messenger.