The async pattern needed to write UWP apps (or simply "Universal apps") is not so easy to grasp, especially in C++. Eric from the Visual C++ team explains how the experimental Coroutines feature available in Visual Studio 2015 helps simplify async UWP code:

Using C++ Coroutines to simplify async UWP code

From the article:

C++ Coroutines can simplify your async code, and make the code easy to understand, write, and maintain...