With the rise of the iphone, two things are becoming more imperative:
- You need to have separate css for handheld devices.
- You need to have a strategy for chunking information on your page. Iphone’s dirty little secret is that the screenshots and tv commercials make the iphone look a lot larger than it is. In fact, it has limited real estate (however cool-looking it is).
For your content to fare well on the iphone, you need to have a way of displaying content in chunks big enough to satisfy surfers yet small enough that it doesn’t require too many Page Downs.
(See also: this teleread post)