I am writing Kotlin/Android at my daily job. I switched from Java to Kotlin very recently.
First, it was the promise that Kotlin gives us. It solves many problems that a Java developer faces on a daily basis --- Null safety and verbosity being on the top. Next, the interop was another selling point.
I don't have to write a class for every single file that I have. Concurrency using Coroutines are easy to follow. List processors like map, reduce, zip etc are a part of the standard library. I know when something can be NULL. Extensions are fun stuff.
I promote Kotlin among my colleagues that work on JVM. They must try this modern language for sure.
Did you have some success with your colleagues so far? Do they have reservations?
It is a success. People are getting more interested when they see the real code. Now two of my colleagues are full-time Kotlin, and four are currently learning Kotlin. We have decided that all our upcoming projects in Android will be 100% Kotlin. My colleagues want to switch mainly because they see how easy and efficient to write Kotlin than Java.
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