Four months after the launch of its latest operating system update, Apple has updated its support page to reveal the iPhone and iPad's iOS 15 installation numbers.
According to the data, 72 percent of all iPhones introduced in the last four years, including the iPhone 13 series, iPhone 12 series, iPhone 11 series and the iPhone X series, are now running iOS 15 and 63 percent of all iPhones are on Apple's latest OS.
Only 26 percent of iPhones released in the past four years are running iOS 14, whereas 30 percent of all iPhones are still running iOS 14. Further, 2 percent of iPhones released in the last four years are on iOS 13 or lower, and 7 percent of all iPhones haven't upgraded to iOS 14 or higher.
The latest OS installation numbers are much lower on iPad. Only 57 percent of iPads released in the last four years are running iPadOS 15, whereas 39 percent are using iPadOS 14 and 4 percent on older versions.
Forty-nine percent of all iPads are currently running iPadOS 15, while 37 and 14 percent are on iPadOS 14 and iPadOS 13 and lower, respectively.
If you compare these numbers to last year's data, it's evident that a lower percentage of users have decided to upgrade to Apple's latest mobile OS. For reference, last year's report showed that 86 percent of iPhones introduced in the previous four years (from the date of the report) were running iOS 14, 14 percent higher than iOS 15's data. Similarly, 84 percent of iPads introduced in the last four years (from the date of the report) were running iPadOS 14, 27 percent higher than iPadOS 15's data.
The cause of this OS update decline is a little unclear. However, it might be because Apple introduced its latest update as 'optional' when it was first released. According to Apple, iOS 14 won't receive new security updates, so users who want the latest security updates will have to jump to iOS 15.