Only if they want to also get more information on the screen. Wednesday's press event, for example, featured demos of an updated OpenTable app for the iPhone that brought in a lot of elements from the iPad version's interface. As for existing apps, they'll work just fine on the new iPhone, even without an update. But they will feature black bars around the edges--on the side for apps running in landscape mode, on the top and bottom in portrait orientation--to fill in the extra screen space. On the bright side, old apps won't need to be stretched or scaled when they run on the iPhone 5.

Not so! It's actually slimmer and lighter than the iPhone 4S, Apple says. The iPhone 5 is just 7.6mm thick, and weighs 112 grams.

No no, dear reader. Plenty of under the hood changes. The iPhone includes Apple's new A6 chip, which the company says is twice as fast as the A5 chip inside the iPhone 4S. (That twice-as-fast claim applies not only to the processor itself but also how the A6 handles graphics compared to its predecessor.)