It seems that Facebook is finally coming to its senses and catching up to basically all of the other chat apps by adding end-to-end encryption to it Messenger. The “secret conversations” feature makes chats visible only to the sender and reader (finally!). This means that anyone other than a sender or a reader, including Facebook itself, law enforcement and criminals cannot read these selected chats.
There’s also another feature of ‘secret conversations’: it lets users set an expiration date for messages. I should mention that none of this is turned on by default – you actually have to enable it each time you use it in order to work. Also, this feature is only available to select few as it’s still in testing, but should be offered to the rest of Facebook very soon.
According to their blog post, ‘secret conversations’ can only be read on one device and rich content like videos, GIFs, making payments, and so on, are not currently supported.
Chanwoo's Weekly Tech 