Kotlin - best interoperability with Java of all JVM languages (except Groovy) - language support for DSLs (in the form of extension function literals) - static

Kotlin - best interoperability with Java of all JVM languages (except Groovy) - language support for DSLs (in the form of extension function literals) - statically typed - type inference - non-nullable types - smart casts - properties - elvis operator - much easier to learn than e.g. Scala but also less expressive