Facebook continues to copy Snap. In the social media giant's mobile chat app, Messenger, users can now post to a feature called Day to broadcast annotated photos and videos of their life that disappear in 24 hours.

That's the same way the Snapchat app's popular Stories tool works.

In the past few months, features that resemble Stories have been unveiled for Facebook's WhatsApp, where it's called Status, and Instagram, where it's also called Stories. Facebook is also testing a version of the product in its flagship social network.

Snap, the owner of Snapchat, held an initial public offering last week, and now has a market value of more than $25 billion.