If you build the iPhone applications, will they come? Overall, Book applications in the Apple App Store have increased nearly 280 percent over the last twelve weeks.

According to O'Reilly Radar report, books applications have dominated the Apple App Store lately. In early April, nearly 11 percent of all apps added to the iPhone application store were included in the Books category. The App Store is nearing one billion downloads, but as this article notes, downloads don't guarantee frequent usage.

Here's more from the article: "Books has surpassed the Utilities category and may soon overtake the Entertainment category. Over the past week, Kindle for iPhone was the top app in the Books category."