Made possible by the watchOS 2 software update, the app lets users read messages and send voice notes and emoji from their wrist.
Users can take advantage of Apple Watch support by downloading the latest version of Facebook Messenger from the App Store.
Native watch support isn't the only new feature, as Messenger now harnesses the multitasking features in iOS 9, so you can chat away while running another app.
Finally, Messenger contacts and convos will now appear within your native search results on iOS.
The Apple Watch version of the app has attracted some negative reviews on the App Store at launch, with users claiming it is unresponsive, but this could be nothing more than teething problems.