> It's 100% interop ensures that you can only implement bits and pieces in Kotlin, not necessarily the entire app. As long as Kotlin is not identical to javac,

> It's 100% interop ensures that you can only implement bits and pieces in Kotlin, not necessarily the entire app. As long as Kotlin is not identical to javac, there is and never will be 100% interop. > Scala has got more things that Kotlin, there is a comparison of features: http://confluence.jetbrains.com/display/Kotlin/Comparison+to.. http://confluence.jetbrains.com/display/Kotlin/Comparison+to.... While this is a valid point (although the comparison is probably outdated) we should keep in mind that years ago, Scala 1.0 (or something like that) was were Kotlin might be today. There are reasons why Scala evolved from a "better Java".