⟩ Suppose when I deployed my XNA app to the xDE, the orientation is in portrait mode, but when I deploy it to a device, it’s in landscape mode.?
The XNA Framework defaults to landscape mode for Windows Phone games, but XDE doesn’t yet support XNA in landscape mode, so portrait mode is the only option there for now. You can set your orientation preferences by using GraphicsDeviceManager settings (SupportedOrientations, PreferredBackBufferHeight, PreferredBackBufferWidth, etc.