Conclusion. In general, because of the May 2019 announcement from Google I would recommend beginners at Android app development start with Kotlin however there are some exceptions where I think Java may be better . There are two scenarios I would recommend learning Java first for Android app development as a beginner.
Read moreShould I skip Java and learn Kotlin?
You don’t need Java knowledge to learn Kotlin or Kotlin knowledge to learn Java. Having said that, If you know Java, that will be helpful when you need to interop with some Java libraries. You can start learning any of Java or Kotlin without prior knowledge of the other.
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