Hi Jan,
I don't think that you can run Camunda on Android. Android uses a kind of Java but it uses a own Virtual Machine (Dalvik until Android 5.0). This virtual machine has its own execution
format and also doesn't provide the same java standard library. So I would not assume that you can run Camunda on it.
Also to receive Messages you would need an external API like the Camunda Rest API which is currently implemented as Web Application for Java Application Servers, so you would also
need to get a runtime container working on android.
I would agree with Christian that I don't see an use case for running Camunda on an Android device. Nevertheless you could run Camunda on an ARM processor as long has you have a
JVM for it. So you could run Camunda on a Raspberry PI or the like.
Cheers,
Sebastian