More than half of iOS devices already using iOS 9
Apple announced that more than half of devices using iOS, already have the latest version of the operating system iOS 9. The official debut on iOS 9 was less than a week. According to Apple it is the most rapid transition to the new version, which the company has observed. For comparison, currently only 21% of all Android devices use Lollipop. We can not deny that Apple has the advantage of centralized control over hardware and software, but this is not the only factor for the rapid updating the iOS.
With iOS 9 Apple expanded the set of supported devices. Among the products that can use the latest version of iOS, are iPhone 4S and iPad 2, which are four years old. Another factor facilitating the update was the reduced size of the installation file. Until recently, many consumers postponed update because of the need to delete applications to free enough memory for the installation file.