People hate it when Facebook changes how the site looks, and really hate it when it changes how the site works. Considering that, the new Facebook iOS app might be the perfect update — to most users, it will be invisible. It doesn't look or function very differently. The layout is the same, with some minor tweaks to messages and photos, and the buttons all do what you expect them to.
But it feels very, very different. It's faster, smoother, and responds instantly when you touch it. That's because instead of redesigning its app, Facebook has rebuilt it.
Facebook's app used to be a webpage rendered inside of an app shell, a less-than-ideal setup that made cross-platform development easier for Facebook but left the app with kludgy functionality and, due to a quirk in the iOS security rules, a much slower experience than if the "site" — the core of the app — were just visited in the iPhone's normal browser.
On the left is a website benchmark with the iPhone's normal browser; on the right, the same benchmark rendered in the Facebook app, which is stuck rendering with a much slower in-app browser. The old Facebook app wasn't just a web browser; it was a slow browser. Facebook sidestepped this issue by writing the new app mostly in native code. It's a real app, in other words.
None of this is to say that the new app is especially good. The tiered layout is still a bit counterintuitive and, at least on iPhone, the entire screen is often filled with just one or two status updates, meaning you'll still be scrolling a looottttt. But for perspective, the old app didn't even scroll smoothly.
The response to the app is more interesting than the app itself, I think. People are ECSTATIC about an update to an app that barely exceeds expectations for the first version, much less version 5.0. There's something of a prisoner/warden dynamic at play here: Facebook could afford to provide a terrible mobile app for over a year because it knew that its users couldn't really leave. Users' expectations were lowered far enough and for long enough that getting app that functions properly felt like a gift from God. Welcome to Planet Facebook, everybody.
In other news, the new Facebook app for Android adds Emoji.