Facebook Messenger

Facebook InstantMessaging app, split off from original core mobile app.

Facebook Messenger (commonly known as Messenger)[5] is a messaging app and platform. Originally developed as Facebook Chat in 2008, the company revamped its messaging service in 2010, and subsequently released standalone iOS and Android apps in August 2011. Over the years, Facebook has released new apps on a variety of different operating systems, launched a dedicated website interface, and separated the messaging functionality from the main Facebook app, requiring users to use the web interface or download one of the standalone apps. https://en.wikipedia.org/wiki/Facebook_Messenger