<p>As there are a few answers of differentiation in between the JAVA and Kotlin, I would be happier to rely on kotlin as it's more precise while developing an android mobile application, imagine we have written 10 lines of codes that consist a few errors and more than 4 attempts has been already done by you and still you are not able to find the solution, that's where kotlin takes the place of JAVA in coding approach, it's more reliable with less coding and accurate results, that's the main objective of choosing the kotlin over JAVA.
That doesn't mean JAVA is not a language to work with, everything has pros and cons, as a kotlin requires less consumption in coding and contain complex coding formulas that can't understand by the humans sometimes, and on the other side java takes a bit longer comparing to the Kotlin, but we can write clean and neat code that can be easy to read and edit for humans.
These are my take aware of 4+ years of experience as a mobile app developer and a marketer who helps businesses in reducing their mobile and web application development cost through my insightful experience, although currently I am associated with a leading mobile app development company Chicago, that runs of similar mantra to my understanding, which is bringing tech to reality.