Apple's developer support page reveals that nearly half of active iPhones and iPads are running the new upgraded iOS 8 just after one day of launch.
Apple's new operating software, iOS 8 was launched on Saturday, and by Sunday it was already installed on 46 percent of devices connecting to Apple's App Store.
Meanwhile, iOS's biggest rival Android is still struggling. The 10-month-old Android KitKat is still working its way to reach the 25 percent mark.
The relatively quick transition isn't out of character for Apple's devices and compares favorably to Google's efforts, however it hasn't been entirely painless.
Many people were unhappily surprised by the large amount of free space that the new upgrade required, and there remains a swathe of important and prominent apps in need of an update to make them work properly with the new iOS, the report said.