PhoneApplicationPage class includes two orientation related properties:
SupportedOrientations attribute allows you to restrict the orientation of the page and, if set to either
Landscape, prevent the orientation from being changed when the device is rotated. If the page is designed to support both portrait and landscape, set
PortraitOrLandscape, which allows the orientation to be switched automatically when the device is rotated.
Orientation property indicates the actual orientation of the page and can be set only at design time. The
Orientation property is discussed in greater detail later in the chapter.