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 moreHow long does it take to learn Kotlin for Android?
If you have programmed before, you’ll likely be able to learn Kotlin fairly quickly. If you know how to program in Java, you will find learning Kotlin relatively easy and should be able to get your head around the basics in a few days to a few weeks .
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