It might seem impossible to believe, but there are other popular mobile games out there besides Rovio's Angry Birds. One is The Heist, which has 60 different brain-teaser games in four puzzle categories, and is a triumph of both style and substance, bringing together striking graphics and an intuitive, elegant UI with puzzles that grow increasingly challenging at each successive level, all topped off by a classic safecracker caper narrative. The Heist's heights are contrasted with The Underwear Is Floating, which is pretty much just about stealing underwear off a clothesline. The apps are the latest to be highlighted by FierceMobileContent's feature, Appealing/Appalling, a weekly spotlight on the best and the worst that mobile developers have to offer. Special feature