According to an App Store Support Page, Apple’s iOS 7 adoption rate is at 74% about three months after the company released the redesigned software to the public. Apple depicts the adoption in the form of a pie chart, and shows iOS 6 at 22% and anything prior to iOS 5 at 4%. It isn’t altogether surprising iOS 7 is at 74%, especially with the speed improvements, redesigned applications, and new security features the update brings to iOS devices.
These numbers appear to be accurate, as analytics firm Chitika reported a similar 74.1% of devices using iOS 7. Apple notes on the bottom of the pie chart that it measured the adoption rate during a 7-day period ending on December, 1, 2013. That number will likely grow as more and more devices begin switching from iOS 6 to 7 during the holiday period and more customers buy devices with iOS 7 installed (though that probably doesn’t count towards the adoption rate).