IOS 7 adoption over 87%, Android KitKat 5% (techcrunch.com)

This seems to be by design. iOS practically forces every update on you whereas you have to really go out of your way to update Android.

Just wait for High-end device like Samsung Galaxy S5, HTC One M8 and Sony Xperia Z2. Apple forces iOS user to upgrade to latest OS because most of the apps in the Apple store will not work if your iPhone or iPad is not updated with the latest version of Android.