Portability
Multi target to JVM, JavaScript, C and standalone VM
Beautiful Syntax
Generics type, lambda/closures, non-nullable type, async/await ...
Concurrency Safe
Built-in immutability and actor model, safe in compile time
Cross-platform UI Framework
Write once run on Android/iOS/Web browser/Desktop
Server-side Framework
Web framework, database ORM, template engine, async/await based IO framewrok ...