Check this David Marcus post for five 2016 Messenger themes, including "Threads are the new apps"
"Facebook’s standalone messaging app, Messenger, has eclipsed 800 million users worldwide. That’s a lot of people, even by Facebook’s standards.Facebook Messenger Tops 800 Million Users | Re/code
The news was shared in a blog post written by Messenger boss David Marcus early Thursday morning. In the spirit of the New Year, Marcus reflected on 2015 and shared a few themes for the year ahead, including what he called “the disappearance of the phone number.” In Facebook’s world, that means the ability to send messages and make calls via your Facebook profile instead of an actual phone number (which you can already do)."