Facebook Messenger is now available on the Windows OS. Facebook Messenger for Windows Phone lets you send stickers and photos as well as share your location in your messages, and group messaging is also supported. Not all features are there yet, though; for example, voice messaging is not supported in this release.
Some of these features are already built into the Windows Phone platform, but with this release, Microsoft will replace that functionality with the Facebook Messenger app. We're likely to see those changes in the upcoming Windows Phone 8.1 update, which should be arriving in April 2014.
Culled From Mashable