You might recall that Apple pushed out iOS 7.0.6 to close a security gap that could have allowed hackers to read email and other communication that was supposed to be encrypted. According to the data from Chitika, the number of iOS 7.0.6 users still doubles the number of iDevice users sporting iOS 7.1. The iOS 7.0.6 update had a 13.3% adoption rate just 48 hours after its release.
Apple's Car Play, formerly known as iOS in the Car, is part of the iOS 7.1 release, as is a number of bug fixes and new capabilities for Siri and the calendar. The newest build of iOS can be installed on the Apple iPhone 4 and higher, and the Apple iPad 2 and higher.
Apple's latest iOS build is found on 17.9% of North American iOS web traffic
source: Chitika via AppleInsider