Xamarin
Xamarin is a cross-platform mobile app development framework that allows developers to build native iOS, Android, and Windows apps using C# and .NET. It provides a single codebase that can be shared across platforms while delivering native performance and user experiences. Xamarin is integrated with Microsoft's development ecosystem and includes tools like Xamarin.Forms for UI development.
Developers should learn Xamarin when they need to build high-performance native mobile apps for multiple platforms while maximizing code reuse and leveraging existing C#/.NET skills. It's particularly useful for enterprise applications, teams with .NET backgrounds, or projects requiring access to platform-specific APIs without sacrificing development efficiency. Xamarin reduces the need to maintain separate codebases for iOS and Android.