Yeah, sure, you probably know a lot. But there's always that movie or star constellation or post-graduate vocabulary word or Wikipedia fact that you can dig into. Here are the six best apps that'll satisfy your insatiable thirst for knowledge.
iOS
Wolfram Alpha
This is an app that transformed itself from joke to recommended download in record time. All it took, in the end, was a price change: Wolfram Alpha's app, now that it costs $2 instead of $50, is a steal. For those of you who aren't familiar with the Wolfram Alpha website, it's what its creators call a "computational knowledge engine." It's part graphing calculator, part trivia repository, and part search engine—albeit for a select set of databases, most of which are academically oriented. Ask it who Justin Bieber is, and it won't know. Ask it to divide the population of Waco, Texas by the number of stars in the observable universe, and it'll give you this admittedly meaningless number in seconds. 2$, iPhone.
Wikipanion
Wikipedia's creators insist that their project is one with lofty intentions; first and foremost, though, it's a site that lets any jerk become an instant expert on anything. Wikipanion makes the process of Knowing It All a good deal faster than it would otherwise be, with a predictive search interface, in-page searching, bookmarking and the like. Its main appeal, though, is that the time from app-tap to answer is extremely short, and its just nicer to look at than the ‘Pedia's mobile interface. Free version is fine, unless you really want to queue materials for reading offline. Free, iPhone.
Wordbook Dictionary
Every iPhone needs a dictionary, and this one is the best (affordable) app on the platform. Lookup is fast and easy, but depth is what makes Wordbook valuable. You get smart spelling suggestions, full pronunciations, etymologies, a thesaurus with added semantic links, a word of the day feature and even a crossword and anagram solver. Start gratuitously (word choice?) and obnoxiously correcting your friends and passing acquaintances, today! $2, iPhone