javafxports host a JavaFX Android community project. It contains instructions on how to run JavaFX applications on Android. The code is available at https://bitbucket.org/javafxports/android-graphics-rt.
Creating JavaFX Applications that also run on Android devices is not that hard. This project contains everything that is required to build a Java(FX) runtime for Android devices, along with instructions on how to create an Android project based on an existing Java Project. You can choose to either build the runtime yourself, or download one in the Downloads section of this project. The brave ones can build their own runtime. -- follow the instructions to build the runtime on Linux and MacOS.