A lot of iPhone developers seem to think that an app's icon should be a scaled down image or highly detailed graphic of some sort, possibly taken from their desktop app. I, albeit having little design sense, think that's the wrong approach. To me, an icon is about representing what your application does in the fewest amount of shapes. Some developers in the store must think the same way I do, as I've found some of the best apps have the simplest icons. For example, the Speed icon consists of three shapes -> a roundrect, a circle and a round-bottomed-triangle (excuse my terminology). Even in black and white you can see how it resembles a dashboard speedometer. I'm not saying that my icon is good (I let Apple do that for me), but it's better than a lot of the crud. Another great icon is that of Things, the to-do list / project management application. It again uses roughly three shapes -> the roundrect, an inner square (or roundrect, depending on how you look at it) and the tick mark. I admit, for some applications it becomes very hard to define in terms of shapes, but it's hard to deny that the simpler icons look best. I'd like to see more application developers thinking about their icon instead of slapping something together and saying "that'll do". There are over ten thousand applications, and a mere handful with icons that don't suck. I'd really like to see that change as iPhone development matures.