Facebook app is miles away from other OS's app! The upload is a pain in the ***, there's no 'What are you doing?' option when posting a status (feeling..., listening to..., watching..., etc.), the News Feed is very limited, I only see few posts compared to the web version, no friend/page suggestions, very bare! I rarely use the app! If it wasn't for People Hub I would've uninstalled this worthless app.
Messenger sucks too. You can't actually switch accounts unlike in IOS and Android! I once logged out of my Facebook app but the Messenger didn't log out, and it seems like there's no option for it at all! Chat heads are useful and I always felt envious of Android and IOS users about it, but it's probably not gonna happen since WP is different, plus the notification feature for Win10 can fill the chat head responsibilities like showing all the text and replying back without opening the app.
That's all.
Microsoft needs to port the Facebook app from the other two OS because from what I see they're already losing. Or let Facebook do the app and collaborate for the people hub feature? Do what it takes you're losing people!!!