Read original post at Michiel Post's Blog
When you're starting Windows 8 / WinRT development in XAML, one of the first things you do is look at the available controls. The default controls shipped with the WinRT XAML framework are ok, but not all scenario's are covered.
If you need more controls, there are some paid control toolkits available. But luckily there are also some state of the art free libraries. NuGet is a great resource to find controls and helper libraries for Windows 8 development.