Xamarin has integrated its cross-platform development tools with Microsoft’s Visual Studio Community 2013, allowing developers to build native Android and iOS apps for free.

The (just released yesterday) Visual Studio 2015 Update 2 installer will install Xamarin for you (it's one of several checkboxes under Cross-Platform Development), and IIRC will install it by ...

Xamarin has been bringing .NET to iOS and Android developers for a number of years, including enabling iOS development from within Visual Studio. Microsoft, of course, has been doing the same for ...