Não da mesma forma que os aplicativos normais do Windows.
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Os possíveis estados de visualização de um aplicativo são fonte: link
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Você pode dividi-los no modo lado a lado
Let’s see how split screen is enabled for a Metro app in Windows 8.
1.You need to open the Metro Start Screen and open your app e.g the Finance App.
2.Left click on the App and hold your mouse button. You will see the app appears in a small window.
3.Drag the app in the small window on either end of the screen horizontally.
4.Open the Metro Screen again and click Desktop.
5.You will now see the Finance App and Desktop simultaneously showing on the screen.
fonte link