Obviously the most important tool is Visual Studio 2012 which is available as Express and the various wonderful SKU’s but along side these there are some great toolkits which will help your Windows 8 escapades no end.

this list will be updated regularly

Calisto

The Calisto Toolkit developed by Tim Heuer adds helper functions and XAML controls, must useful are the controls to help deliver the settings fly out.

https://github.com/timheuer/callisto/tree/master/src/Callisto

Or you can download and install Callisto from Visual Studio Gallery

WinRT XAML toolkit

Provides a set of XAML extensions to help delivery of Windows 8 Store applications,

http://jupitertoolkit.codeplex.com/

Nuget Package Name  winrtxamltoolkit

Code Snippets

A set of code snippets for C#,VB,JavaScript and C++, the snippets allow a variety of standard WinRT actions to be done simply such as send SMS, write to

https://windows8snippets.codeplex.com/

provide a base set of canned code for Windows 8 Store applications

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