What is Xamarin ?

Xamarin is a Microsoft-owned San Francisco-based software company founded in May 2011 by the engineers that created Mono, Xamarin.Android and Xamarin.iOS, which are cross-platform implementations of the Common Language Infrastructure and Common Language Specifications.

With a C#-shared codebase, developers can use Xamarin tools to write native Android, iOS, and Windows apps with native user interfaces and share code across multiple platforms, including Windows and macOS.[4] According to Xamarin, over 1.4 million developers were using Xamarin's products in 120 countries around the world as of April 2017.

In December 2012, Xamarin released Xamarin.Mac,[18] a plugin for the existing MonoDevelop Integrated development environment (IDE), which allows developers to build C#-based applications for the Apple's macOS operating system and package them for publishing via the App Store. In February 2013, Xamarin announced the release of Xamarin 2.0.[19] The release included two main components: Xamarin Studio, a re-branding of its open-source IDE Monodevelop;[20] and integration with Visual Studio, Microsoft's IDE for the .NET Framework, allowing Visual Studio to be used for creating applications for Android and iOS, as well as for Windows.