As far as I understand it, Windows Phone 7's API is Silverlight with a few restrictions related to screen size and the like.
I haven't coded anything for Windows CE, but making a Silverlight app for Windows Phone 7 is about a difficult as making a WCF app for Windows, or an ASP.Net app for the web.
I haven't coded anything for Windows CE, but making a Silverlight app for Windows Phone 7 is about a difficult as making a WCF app for Windows, or an ASP.Net app for the web.