The rollout of Facebook Messenger "secret conversations" is reportedly complete, providing end-to-end encryption and some Snapchat-like features to the 900 million users of the social network's messaging app.

In July, Facebook announced that it was testing end-to-end encryption with select users to better support conversations about sensitive topics. Now, as Wired points out, Secret Conversations is live for everyone.

As David Marcus, Head of Messenger, explained in July, Secret Conversations mode "means the messages are intended just for you and the other person—not for anyone else, including us." Meanwhile, it will also "enable you to set a timer to control how long each message you send stays visible in the conversation on both devices (yours and your recipient's)."

"To be clear, your existing 'regular' messages and calls on Messenger already benefit from strong security systems as Messenger uses secure communications channels — just like banking services — all around," Marcus continued. "But we're rolling out this additional capability as an option for the most sensitive conversations you might need to have."

Starting a secret conversation is optional because end-to-end encryption breaks some features in Messenger, like using it across multiple devices, archiving past conversations, and sending things like animated GIFs.

But it could be good for "discussing private information like an illness or a health issue with trusted friends and family, or sending financial information to an accountant," Facebook says.

On iOS, navigate to the "Me" tab on the bottom right of Facebook Messenger, scroll to Secret Conversations, and toggle it on. On Android, hit the chat head icon on the top right, scroll to Secret Conversations, and toggle it on. Then, when you go to start a new message, you will see a "Secret" option on the top right. Tap that to start a clandestine chat.

Covert conversations are identified by the black-and-white lock icon, which replaces the usual blue-and-white Messenger logo next to the person's profile picture.

The new tool employs Signal Protocol, which also powers creator Open Whisper System's private messaging app Signal, as well as Facebook-owned WhatsApp and Google Allo.