Windows 8 Release Preview provides Metro style apps with the ability to run app code, even when the app is suspended, by using background tasks.

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Windows 8 Release Preview provides Metro style apps with the ability to run app code, even when the app is suspended, by using background tasks. This paper describes the programming model to create background tasks, resource management policies for background tasks, and built-in user controls that allow the user to control per-app background task activity by using lock screen personalization. Some familiarity with Metro style app development is assumed.
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