Nearly three quarters of all iOS users are running the latest major version of Apples operating system, less than three months after its debut. One simple reason: Apple put out new iPhones in September and new iPads in October, both of which ship with iOS 7. The operating system also saw the fastest adoption of any major Apple software release. We still dont quite know how many new iPhones and iPads Apples sold since iOS 7 arrived in September (the company reports its current quarter next month).