Discover is a free gem that turns your iPhone or iPod Touch into a wireless flash drive combined with a file viewer. With plenty of features, the only real downside to Discover is the ads and some minor lag—but at least you won’t hear anyone complaining about the price.

Good Reader is a document reader that stands out because it can read mega-sized files (200+ Mb!). The idea is wonderful, but the slow speeds and long load times make this one quite average.