Can I use it on any board?

Hardware Home Automation
1

Is it available on any board that supports the JVM?

2

Yes:

openHAB 2 is based on the Eclipse SmartHome framework and is fully written in Java. As such, it only depends on a Java Virtual Machine, which is available for many platforms. openHAB can be executed on different versions of Mac OS X and Windows and many different variants of Linux (Ubuntu, Raspbian, …).

http://docs.openhab.org/installation/index.html