Windows 8 & Windows Phone Cross Platform Development Resources
With development of apps for Windows 8 and Windows Phone 8 getting much closer but still not being the same, there are some good resources out there in regards to creating projects that share a maximum amount of code between the two platforms.
The cornerstone of Windows 8 and Windows Phone 8 cross platform development are portable class libraries and MVVM pattern that help separate UI and logic.
The main area on the topic on MSDN including articles and code samples is here: http://msdn.microsoft.com/en-us/library/windowsphone/develop/jj714089(v=vs.105).aspx
There is also a section on the “Microsoft Virtual Academy” called “Building Apps for Windows Phone 8” https://www.microsoftvirtualacademy.com/tracks/building-apps-for-windows-phone-8-jump-start that has a Module (#19) on this.
You can sign up to the Microsoft Virtual Academy for free using any Microsoft ID.
Furthermore, the following sessions on the topic were presented at the Build conference last fall in Seattle:
“How to Leverage your Code across WP8 and Windows 8”: http://channel9.msdn.com/Events/Build/2012/3-043
Link provided by Stuart Lodge: “Create Cross-platform Apps using Portable Class Libraries”: http://channel9.msdn.com/Events/Build/2012/3-004
Happy coding (and code reusing)!