Joe: I definitely agree with the general philosophy that iPhone apps should do one thing well, but it doesn't apply to Facebook overall—people demanded that the app have all the features of the website. To reconcile the need for simplicity with this demand for every feature, I broke the app into sub-apps, and then pared each of those down to make them as focused as they could be. That's what inspired the Home-screen grid in Facebook 3.0.
Figure 7-24. Three drafts of the top-level screen for Facebook 3.0, inspired by the springboard grid of the iPhone Home screen. The left mockup introduced the concept and overall layout, evolving into the final design at right.
Facebook is really a platform in itself, and I realized that a lot of the core apps that are built into the iPhone are also built into Facebook itself: photos, address book, notes, and so on. The more I thought about it, the more it felt like Facebook was this parallel version of the iPhone itself, and I thought people might understand it that way if I used the same Home-screen approach. At the time, I felt it was a little risky, and I wasn't sure that people would like it, but I was pleasantly surprised by how well people took to it. It's something they're used to from the iPhone Home screen, so there was nothing new to learn there.
Laying out a grid of nine buttons wasn't a big deal, of course, but adding Home-screen editing was a bit of work. Just like the iPhone Home screen, the Facebook app lets you customize and reorder icons: tap and hold an icon, the icons start jiggling, and you can move them around. Apple broke that ground on the Home-screen springboard, so I felt comfortable doing it in the app. As I was working on it, though, I wondered what Apple's designers were thinking about what percentage of users were going to figure out Home screen editing. I'm guessing there are a lot of people with iPhones that haven't figured out that they can do that by holding down an icon.