Apple's App Store has hit another milestone, with the online retail outfit for iPhone and iPod touch programs delivering 500 million apps. Furthermore, 15,000 apps are no available for download from the site.

Apple released the news in an advertisement on Friday that ran in the New York Times, Wall Street Journal and USA Today.

A little more than a month ago Apple had hit the 300 million download mark and boasted 10,000 apps available in the App Store. The App Store opened just over six months ago on July 11, 2008 with 500 apps available for download.