Well, it would be nice to know why your components are defaulting to mobile skins on desktop. That is probably a question for the developer mailing list.
If I was in your shoes, I would be sharing a single codebase between desktop and mobile, and while it's a little bit brute force, just use the @media query in your main css file: @media (os-platform: "IOS") or (os-platform: "android") { s|Button { skinClass:ClassReference("spark.skins.mobile.ButtonSkin"); } } @media (os-platform: "Macintosh") or (os-platform: "Windows") { s|Button { skinClass:ClassReference("spark.skins.spark.ButtonSkin"); } }