How To Close Windows 8 Apps

Generally, App/Application in Windows 8 don't have the exit menu, because Windows 8 has ability to handle the apps to reducing CPU and Memory resources when user leave the App and open another/new App. (Windows 8 Metro  automatically suspend their CPU and RAM usage when they lose focus).

You still can close/exit the Apps manually,.

To do manual close/exit the apps in Windows 8 :

If using Mouse :
Move the mouse cursor to the top until the cursor icon change to (hand icon), click and drag the App to the bottom of the screen.

If using Touch Screen :

Touch and Swipe from the top of the screen,  grab the app and then drag it down to the bottom of the screen.

Using Keyboard shortcut:
Press Alt+F4 to close the App.

See Also:
How to make dummy texts
How to share file through internet with easy way
How to Enter Product Key In Windows 8
Opening New Notepad In Windows 8