Many Google teams have also been on a similar journey from Java to Kotlin for both Android and the server-side, culminating in over 11m lines of Kotlin code (as of October 2022).

Still, Oracle, on behalf of Sun, is arguing that Java is a mobile operating system competitor against Android, and that Google is using Java-derived technologies without a proper license.

Epic Games, the maker of Fortnite, filed a lawsuit against Google three years ago, alleging that Google's Android app store has been protected by anticompetitive barriers.

That’s why Android app makers have embraced Kotlin as Java 2.0. Based on the fundamentals of Java, Kotlin is a new-school language that fixes a lot of the problems developers have with Java.