iOS 6 was installed on 15% of iPhones and iPads in the first 24 hours of the mobile operating system's availability, according to Chitika Insights, which gets its data from millions of mobile ad impressions it measures on its network.

Apple released iOS 6 on September 19 over the air and through iTunes to mainly positive reviews, though the upgrade had initial WiFi-related hiccups and some users are down on Apples switch from Google Maps to its own Maps app. Apple has touted improved Siri voice capabilities, turn-by-turn navigation and better Facebook integration in iOS 6, which boasts hundreds of new features that iPhone 5 users will soon get their hands on.

It took iOS 5 five days to wind up on 20% of devices, so obviously iOS 6 is off to a speedier start.

Chitika points out that Androids newest OS, Jelly Bean (version 4.1), only grabbed 1.5% adoption during its first two months on the market.