FREE Visual Studio Community 2013, code for Windows, Android, and iOS.
Visual Studio Community 2013 is a new edition that enables you to unleash the full power of Visual Studio to develop cross-platform solutions. Create apps in one unified IDE. Get Visual Studio extensions that incorporate new languages, features, and development tools into this IDE. (These extensions are available from the Visual Studio Gallery.) Find out more details about Visual Studio Community 2013 here.
Introducing Visual Studio Community 2013