iOS 7 adoption continues to grow, with Apple seeing the operating system on 87 percent of devices connected to the App Store, according to Apple's App Store developer support page.



From MacRumors:

The numbers come seven months after the operating system's original release and two months ahead of the expected preview of iOS 8 at Apple's Worldwide Developers Conference in two month's time. Apple has traditionally seen speedy adoption of its new iOS releases because it makes it easy for customers to upgrade to the new operating system without too much trouble, and it's likely that iOS 8 will see similar adoption after its expected release this fall.

  iOS 7 Adoption up to 87% Ahead of WWDCs Likely iOS 8 Announcement