How Do You Use Facebook on Your Phone?S

I thought one of the first things people do when they buy a smartphone is download the Facebook App for iOS or Android and just never look back. Turns out I'm wrong! Mark Zuckerberg says people actually use the Facebook mobile website more than Facebook apps.

What!? Here's what Zuck told Matt Lauer of the Today Show:

And the thing that I think a lot of people don't think about is that there are actually more people in the world using Facebook on mobile Web, right, so not using the apps on iOS or Android, but actually just going to a browser on a phone. There are more people doing that than the iPhone and all of Android phones combined, right?

That's pretty impressive! Is there a reason people prefer the mobile website over an app? I know for other sites—IMDB, Wikipedia—I just hop on the browser instead of the app but something as connected as Facebook would seem to require an app. How do you guys use Facebook on your phone? And what do you mainly use Facebook on your phone for?