Diacarta
Looking for a more elegant way to plan your days than the iPhone's built-in Calendar app? Give Diacarta ($2) a try. Based around a novel interface that offers two 12-hour periods — AM and PM — for each day, users drag-and-drop from a library of more than 50 graphic icons on to screen, and move it around the edges of the central clock to associate it with a particular time. Simple, elegant, and well-designed, it's well worth the two bucks even if your day planning consists of nothing but "buying beer," "grilling out," and "drinking beer."