Use Instagram to Chat With Friends on Facebook Messenger

Facebook began integrating its Instagram and Messenger apps, allowing users of the services to directly communicate with each other
The two apps operate separately, with no direct communication between them. Facebook said it would also add roughly 10 features to Instagram that were previously exclusive to Messenger, such as group video watch sessions, an ephemeral messaging mode and selfie stickers.
Mark Zuckerberg, Facebook’s chief executive, announced last year that he planned to knit together the company’s three messaging apps, Messenger, Instagram and WhatsApp, noting that more people were communicating privately online. That’s a marked difference from the early days of Facebook, when users publicly posted to their digital walls.