Update README.md

Author: thomasnield

README.md

@@ -4,6 +4,8 @@ Learn more about RxJava on the <a href="https://github.com/ReactiveX/RxJava/wiki
 
 RxJavaFX is a simple API to convert JavaFX events into RxJava Observables and vice versa. It also has a scheduler to safely move emissions to the JavaFX Event Dispatch Thread. 
 
+NOTE: To use with [Kotlin](http://kotlinlang.org/), check out [RxKotlinFX](https://github.com/thomasnield/RxKotlinFX) to leverage this library with extension functions and additional operators. 
+
 ## Master Build Status
 
 <a href='https://travis-ci.org/ReactiveX/RxJavaFX/builds'><img src='https://travis-ci.org/ReactiveX/RxJavaFX.svg?branch=0.x'></a>