Articles
Accessibility Resources for Developers (Portal with many links)
http://social.technet.microsoft.com/wiki/contents/articles/28725.accessibility-resources-for-developers.aspx
Accessibility for Windows Runtime apps using C#/VB/C++ and XAML
http://msdn.microsoft.com/en-us/library/windows/apps/hh452680.aspx
Accessibility for Windows Runtime apps using JavaScript and HTML
http://msdn.microsoft.com/en-us/library/windows/apps/hh452681.aspx
Make your Windows 8.1 app accessible. Reach more customers!
http://blogs.windows.com/buildingapps/2013/10/22/make-your-windows-8-1-app-accessible-reach-more-customers/
Testing for accessibility in Windows Store apps
http://blogs.windows.com/buildingapps/2014/03/25/testing-for-accessibility-in-windows-store-apps/
Using Narrator on the Desktop
http://windows.microsoft.com/en-us/windows/hear-text-read-aloud-narrator#1TC=windows-8
Using Narrator on the Phone
http://www.windowsphone.com/en-us/how-to/wp8/settings-and-personalization/use-narrator-on-my-phone
Microsoft Accessibility Standard (MAS)
http://enable/RelatedResources/MAS%20v2/MAS%20v2%20Final.docx
Channel 9 Videos
Introduction to Accessibility
http://channel9.msdn.com/Series/Introducing-Windows-8/Introduction-to-Accessibility
Designing with Narrator in mind
http://channel9.msdn.com/Series/Introducing-Windows-8/Narrator
How to Build an Accessible Windows 8.1 App
http://channel9.msdn.com/Events/Build/2013/2-001
Lessons Learned from Building Alarms and Calculator for Windows 8.1
http://channel9.msdn.com/Events/Build/2013/2-060
Tips and Tricks for Designing a Great Accessibility Experience for Your App
http://channel9.msdn.com/events/Build/2014/2-539