The Template samples:

http://code.msdn.microsoft.com/wpapps/Universal-Windows-app-cb3248c3

To use the templates you must be running Windows 8.1 and  upgrade your Visual Studio 2013 to:

image

Now your file new project dialog will look like the following, you will see that there is a new category called Universal Apps, and four templates.

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End of the beginning of the universal app exploration.