Apple has surpassed a milestone 10 billion downloads at its App Store,the company has announced in a celebratory billboard splashed at its website.

The company had been running a big ticker as it marched toward the number. Apple’s asking visitors to apple.com to “come back to this page later” to see who won a marketing contest in which whoever downloaded the 10 billionth app could win a $10,000 iTunes gift card.

The App Store first launched in 2008. It now has apps in 20 categories including games, business, news, sports, health, reference and travel. Apple also recently opened a Mac App Store, with about a thousand free and paid apps for Mac computers. By comparison, there are well over 300,000 iPhone apps and more than 40,000 native iPad apps.

Apple says the 10 billionth app downloaded — Paper Glider — was purchased by Gail Davis of Orpington, Kent in the U.K., who will receive the iTunes gift card. “The App Store has surpassed our wildest dreams,” Phil Schiller, Apple’s senior vice president of product marketing, said in a statement, noting that 7 billion apps were downloaded in just the last year.

Paper Glider is a simple game app (free, at least today). You flick and fly a paper plane to see how far you can make it go. It’s gotten mixed reviews by users in the App Store.

(Source: USA Today)