iOS 9 already on 50% of devices, Apple touts fastest ever adoption

Apple has announced today that iPhone and iPad owners have been more eager to update their devices to a new version of iOS than ever before, with iOS 9 – released to the public just five days ago – now installed on more than 50 percent of all iOS devices.
Senior VP of Marketing at Apple, Phil Schiller, said that the new operating system is "off to an amazing start, on pace to be downloaded by more users than any other software release in Apple’s history."
History tells us that iOS update adoption tends to hit 50 to 70 percent reasonably quickly, with iOS 8 getting installed on 46% percent of devices within a week of its launch. Installation rates tend to slow after this point, but within a few months the vast majority of iOS users are running the latest version of the OS.
Apple also announced that the iPhone 6s and 6s Plus will be available in the company's retail stores on September 25th from 8:00am local time. This is the same date customers' online pre-orders should start arriving at their doorsteps, though if you haven't ordered one just yet, you'll be able to queue up to purchase one at your local store on launch day.