Windows-8.1

You need Windows 8 in order to develop for Windows Phone 8. Windows 7 won’t work. But avoid Windows 8, it is confusing. Use Windows 8.1 instead. And boot directly into the “Desktop”. Avoid the annoying “Start” thing. Good news: the upgrade from 8 to 8.1 is free. You should know that there are many “flavors” of Windows: “RT”, “Regular”, “Pro”, “Enterprise”… just get the “Pro”. RT (Runtime) is the new name for Metro. ...