The chief executive confirmed the milestone during the company's World Wide Developers Conference (WWDC) in San Francisco today.
Cook also revealed that more than $5 billion has been paid out to the creators of iPhone and iPad apps since the service launched, and announced plans to bring the App Store to an additional 32 countries.
"For Apple, and I suspect many of you, our goal has always been to do great work, and in doing so, make a difference in other people's lives," said Cook.
"Nothing makes us happier than seeing hundreds of thousands of developers around the world using our hardware and our software to create and share their latest and greatest ideas."
Apple's App Store will now be available in 155 territories in total.
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