Developing a product that lets you easily create cross-platform native apps (iOS and Android) is a pretty exhausting task. But Xamarin has done a fantastic job, Xamarin is redefining cross platform development, providing the advantages of native UI, access to device features, and native performance coupled with the time-to-market advantages of code sharing and reuse. Similar with .NET, Xamarin also use a class library in performance, so you can create a class library project that can be reused even though cross-platform. For you who not having much experience with mobile apps before, Xamarin provides convenience to perform the installation, all will convert according with the desired platform. Xamarin also provides a plug in that can be used in visual studio. To make sure the process of development, testing and publish goes well, Xamarin provides a platform emulator and it could be appropriated for any platform. If you are a C# developer and looking to get into mobile, common and try the Xamarin. it will challenge you!