How to protect Windows Phone 8 game from being recompiled? We are facing the problem: someone repacks our XAP, modifies WMAppManifest.xml, and posts it somewhere on the internet. How does he do this? When I download legal XAP from Windows Phone Marketplace it is not the original XAP built by me, but rather package encrypted by Microsoft, so it cannot be simply unzipped. How come that someone can crack it? Does he use dowloaded package, or rather extract installed and decrypted package from his phone? On Android platform I check integrity in runtime by comparing actual package-name/signature with intended. It's very simple and effective, though one still can decompile (obscured) Assembly-CSharp.dll and cut this check off. How can I detect similar tampering on Windows Phone 8? All the assemblies I see in built package are not signed (strongly named).