When talking about Kotlin and Java, both are good. But Kotlin, again, gives much more opportunities. Kotlin-JS gives you browser applications, Kotlin-Native allows to compile to native application (and interop with them).
Read moreWhich is easy Kotlin or JavaScript?
Of course Kotlin and java have very much in common but I was surprised to find its similarities with Javascript . I was able to relate many concepts of Kotlin with that of Javascript and it made my learning much easier.
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