The encryption debate is in full swing these days, but despite the ire of opposing parties the world over, more and more tech companies are embracing end-to-end encryption for users, which allows every single user interaction in a given app to be so well encrypted that even the company behind the encryption can't crack it open and reveal what was said and done. Apps like Telegram have built their legacy on this feature, WhatsApp boasts the feature, and now Facebook Messenger is finally jumping fully on board. Secret Conversations, a feature that lets users encrypt chosen conversations end to end, has been in a limited rollout for a while now, and is finally available to all of Facebook Messenger's users worldwide.
When using the feature, the first thing most people will notice is that a large number of features are disabled. You can no longer send GIF files or videos, for example. Conversations are basically down to text, pictures, and stickers, since end-to-end encryption of larger volumes of data can put a strain on both devices involved, and even on the networks and servers involved, with enough users on board. Still, if security is a concern, this isn't nearly enough to deter use of Secret Conversations. The conversations can only work if both users have the latest update to Facebook Messenger, and either user can set a self-destruct timer on messages. The conversations will only be available on the device they originated from, and will not follow an account from device to device. They can, of course, be deleted from your device on demand with no trace left behind.
The feature will be strictly opt-in, which seems to have drawn criticism from privacy advocates. While the feature being opt-in means that it really only targets users who know what encryption is, the fact that it's available to all users at all is a big privacy win, and it means that the users who aren't quite as concerned over security can still enjoy Facebook Messenger's full feature set, most of which is disabled inside of secret conversations to keep operations minimal and help ensure security.