With 10 million downloads during its first weekend despite what now sounds like a ridiculously small catalogue of 500 apps, the App Store got off to a flying start in July 2008.
That showed the folly of Apple's original position that iPhone users would be satisfied with web apps.
While web apps are fine for some purposes, others require native apps for performance or the ability to work completely disconnected - early US iPhone users may have enjoyed unlimited data plans from AT&T, but globally that was the exception rather than the rule.
One year later the totals reached 5 billion downloads and 225,000 apps - both figures had been boosted by the arrival of the iPad.
March 2012 saw the 25 billionth app download, followed by an impressive 2 billion downloads in December 2012.
It took just over a year to double the aggregate downloads: the 50 billion milestone was reached in May 2013, and by the fifth anniversary more than 900,000 apps .
To mark the anniversary, Apple is making available "five landmark games and five groundbreaking apps" at no charge for a limited time.