Migration Windows Store App based on 8.1. does it has backward compatibility with 8?

Question

As you know Microsoft Build conference is running on this week.

I hardly find whether 8.1 based store app has backward compatibility with 8 based app or not.

Answer 1

No, once you migrate an app to Windows 8.1 Preview, the minimum OS version in the manifest will be set to 6.3.0 which will only allow it to run on 8.1. Windows 8 apps, on the other hand, will run on both 8 and 8.1.

There are more migration issues than the view state matters. See //build 2013 talk http://channel9.msdn.com/Events/Build/2013/3-077 for the details.