“We wanted to make sure we’re doing what we can to make messaging private and secure,” Messenger product manager Tony Leach affirmed. Secret conversation mode will only be available on iOS and Android, not in Messenger.com, Facebook chat, or the desktop Messenger app , at least for now. Facebook’s secret conversations will use a protocol called Signal, created by the non-profit Open Whisper Systems.
Facebook encrypts messages only when users choose to turn on secret conversations manually. This will work only from a single device and the user will have to pick which one. Secret conversations won’t support gifs, video, or payments yet. A self-destruct time for messages can be set. As other communication provider had, Facebook will confront with objections from the part of encryption opponents.