The company said on Friday that it had reached the milestone when a 13-year old from Connecticut made a download.
The App Store was first developed to allow Apple to control the sale of third-party software for the iPhone and iPod touch, as well as give developers a single marketplace to distribute their software.
Apple said that the store is now available in 77 countries, and offers more than 35,000 applications. The store reached the download milestone much faster than the iTunes music store, which took nearly three years to serve up its billionth download.
"The revolutionary App Store has been a phenomenal hit with iPhone and iPod touch users around the world, and we'd like to thank our customers and developers for helping us achieve the astonishing milestone of one billion apps downloaded," said Phil Schiller, senior vice president of worldwide marketing at Apple, in a statement.
The user who downloaded the billionth piece of software, Connor Mulcahey, will be given a $10,000 gift card for the store along with a new MacBook Pro, a Time Capsule backup drive and an iPod touch.
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