But as we move further into the mobile age, it’s clear that Facebook is on the defensive. The problem isn’t with the Facebook mobile app per se, which is elegantly executed and does a fine job of recreating the web experience on a phone or tablet. Rather, the problem is that people don’t want a web-style social network on their mobile devices. They want a simpler, faster, less public, and more intimate way to share with only close friends, the ones they care about the most. They want to swap pictures. They want to say, “I’m here.” They want pieces of Facebook, but not the entire package at once.
From: Wired Top Stories