Are you developing an app that will be sending and receiving data from the Internet? Or will it be displaying a message or working with the file system? Learn more about when asynchronous programming is needed to help your apps remain responsive as they complete tasks that may take some time.
This //BUILD video helps demystify Async Programming for both C# and Visual Basic. With these related topics:
This article from C# Corner gives you a basic step by step dev overview on how Asyn Prog works in Windows 8.
GENERATIONAPP IS HAS ALL YOU WILL EVER NEED TO BUILD YOUR FIRST WIN8/WINPHONE APP
You will always have this list of Windows 8 resources at your disposal: