How can I turn off 3D / parallax wallpaper on iOS 7?
By default, iOS 7 creates a parallax effect on the home and lock screens, giving the illusion of 3D when the device is moved. This can be interesting, or at times annoying and a waste of battery power. If you prefer to keep the background wallpapers flat behind icons, this is how to turn parallax off.
Navigate to the iOS 7 Settings -> General -> Accessibility -> Reduce Motion -> ON.
3D motion behind alerts and icons is now disabled. Reduce Motion will also replace the app zoom effect with a quick fade in iOS 7.0.3 or later.