It doesn't fragment the community as you can call kotlin code from java and vice versa. Seamlessly.
Kotlin is great in that it brings Java 8 features to Java 6(lambda expressions, functional programming, etc.) and more. It's a boon to productivity and makes programming in the Java ecosystem fun again.
There is a sometimes increase in compiling speed but it's very marginal and the method counts increase with the transpiling but it's not noticable until the app get's on the larger side.
Kotlin is great in that it brings Java 8 features to Java 6(lambda expressions, functional programming, etc.) and more. It's a boon to productivity and makes programming in the Java ecosystem fun again.
There is a sometimes increase in compiling speed but it's very marginal and the method counts increase with the transpiling but it's not noticable until the app get's on the larger side.