Robert is joined this week by Francis Cheung and Blaine Wastell of the Microsoft Patterns and Practices team. They show us Prism for Windows Store Apps. This project provides guidance to developers who want to create a Windows Store business app using C#, XAML, the Windows Runtime, and modern development practices. The guidance helps you implement MVVM with navigation and app life cycle management, validation, managed application data, and more. It also provides guidance on testing your app and tuning its performance. Francis and Blaine show how easy it is to get started using Prism in your Windows Store apps.