Xamarin
.NET & C#Cross-platform mobile development with .NET
xamarincsharpmobilecross-platform
Cross-platform mobile development with .NET
Free, cross-platform, open source developer platform
Cross-platform framework for building web apps and services
Object-database mapper for .NET
Build interactive web UIs using C# instead of JavaScript
Curated list of C++ resources and libraries
Cross-platform C# editor with IntelliSense