Kotlin is the new language for Android development.

From Wikipedia:

Kotlin is a statically-typed programming language that runs on the Java Virtual Machine and also can be compiled to JavaScript source code. Its primary development is from a team of JetBrains programmers based in Saint Petersburg, Russia (the name comes from Kotlin Island, near St. Petersburg).[3] While the syntax is not compatible with Java, Kotlin is designed to interoperate with Java code and is reliant on Java code from the existing Java Class Library, such as the collections framework. Kotlin is similar to Apple's Swift.[4]

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Development lead Andrey Breslav has said that Kotlin is designed to be an industrial-strength object-oriented language, and a "better language" than Java, but still be fully interoperable with Java code, allowing companies to make a gradual migration from Java to Kotlin.[10]

The Kotlin site: "Statically typed programming language for modern multiplatform applications" Here.