Wikipedia (free)

Sure, Wikipedia has a Web site, but this app puts that avalanche of information right on your home screen. Like on the Web site, the app's first page shows a featured articles, "on this day" content, and recent news. When reading an article you swipe to the left to read more, an action that worked great on the touch screen. The app displays photos, media content, and everything else you'd expect, but you also get a button to view the same page on the actual site.