The update isn't spreading as quickly as iOS 6 or 7. There's blame to go around.
by Andrew Cunningham - Oct 9 2014
If you follow Apple news closely, at some point in the last week you've probably seen the graph above. It's from Apple's Developer Support page, and the company calculates the figure by looking at the iOS versions of devices accessing the App Store. Like Google's analogous developer dashboard for Android, it's meant to give developers a broad look at OS usage so they can use that data to determine which OSes to support with their apps.
The problem with the graph above isn't that it shows iOS 8 and iOS 7 with the same amount of share, but that the number for iOS 8 has climbed just a single percentage point since the last measurement was taken on September 21. Apple's data mirrors what a number of other independent firms have been claiming virtually since launch day—Chitika's data shows that iOS 8 had rolled out to 7.3 percent of the iOS userbase after 24 hours of availability, while iOS 7 had already hit 18.2 percent in the first 24 hours after its launch. More recent data from Fiksu shows an adoption curve closer to iOS 5 (the last version you needed iTunes to upgrade to) than to iOS 6 or iOS 7
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