The current UIKit.UIInterfaceOrientation of the device.
This value represents the rotation of the interface necessary to keep the interface upright.
Note that in portrait modes, the UIViewController.UIInterfaceOrientation will be the opposite of the UIDevice.Orientation. For example, if the device is rotated clockwise from upright so that it is in portrait mode with the home button on the left, the value of the UIKit.UIInterfaceOrientation will be UIInterfaceOrientation.LandscapeLeft but the value of UIDevice.Orientation will be UIDeviceOrientation.LandscapeRight.