Flyouts in Windows Store app
What are Flyouts in Windows Store app.
Flyouts
Flyouts show temporary, dismissable UI related to what the user is currently doing. For example, you can use flyouts to ask the user to confirm an action, to show a drop-down menu from a button the app bar, or to show more details about an item. Flyouts are different from message dialogs in that you should show a flyout only in response to a user tap or click, and you should always dismiss the flyout when the user taps outside of it; you should show a message dialog only when you need to interrupt the user and demand some kind of interaction.

In the example above, the app stays active, and the user can tap the button or tap outside the flyout to dismiss it.