The App Store’s Top Free, Paid, and Grossing charts are probably the most effective aspect of the App Store – too effective. Top charts are common to all forms of media, from The New York Times’ bestsellers list of books to Billboard’s top ten lists for music. The popularity of top charts is simple: people want to know what other people like. On the App Store, top charts, which exist for the store as a whole and for each category, do just that – they help people discover what is popular.
I credit the top charts for a significant portion of Portfolio’s success. Later apps that have not been able to gain the same traction on them have been nowhere near as successful.