Xamarin is a cross-platform mobile app development platform that enables developers to create native iOS, Android, and Windows apps in a single shared C# codebase. It allows developers to share up to 90% of their code across platforms, making it a great choice for developing apps that target multiple platforms.
For example, a developer can use Xamarin to create a cross-platform app that runs on both iOS and Android. The shared codebase allows the developer to reuse the same code for both platforms, while still being able to customize the UI and UX for each platform. This makes it easier and faster to develop apps for multiple platforms.