Microsoft was clearly being cautious when it said Facebook Messenger would be available for Windows Phone within a few weeks of Mobile World Congress -- it's already here, just over a week later. The app offers much of Facebook's familiar chat experience, including group conversations, photo sharing and (of course) stickers. However, are a few missing features in this first revision. There aren't any voice messaging options, and chat heads aren't around to let you quickly jump between active discussions. If those absences aren't make-or-break for you, though, Messenger is ready and waiting at the Windows Phone Store.