It actually is not. We have a separate Android SDK for Android applications.
The Java SDK uses a version of Netty that requires Java NIO functions not present in the Android VM - even the most recent version of Netty just started claiming to work on Android, but this functionality is untested by the Netty team.
There are also some Class loading issues -- the Jackson parser we use is not the same version as the one required by Android and this causes conflicts at runtime.
Hope this answers your questions.