Man, why the heck are they trying to split everything off into their own apps? If I am using the main app to browse my feed and I get a message, why the heck do I want to swap to another app to answer it?
You don't. Just like when you're browsing HN and you get a message you don't want to swap to another app to answer it. That's why the separated Facebook chat app uses message bubbles that you can answer in any app:
I had no idea they'd managed to make that work for iOS, that's awesome. Definitely agree, FB chat bubbles for Android are one of the best user experiences I've seen.
http://cdn.cultofmac.com/wp-content/uploads/2013/04/Screen-S...
Honestly, it's brilliant, and the sole reason I use Facebook chat for most of my communications.