Apple's App Store has seen 30 billion downloads – generating US$5 billion in revenue for iOS app developers – in the four years since it was launched, apps analytics firm Distimo noted.

The App Store was launched on 10 July 2008 as an update to iTunes with just 500 apps. The number of apps on the App Store now, according to Apple, stands at more than 650,000, making it the largest store globally.

More than 150,000 publishers are developing apps for iOS, with 3.5 million downloads of titles in the top 100 US free charts every day in June 2012, Distimo said.

Daily volume of downloads has increased by 49 percent compared to two years ago.