Hello!
Right now it is windows only.
In case you are interested, an Android version is currently under development.
The base SDK we have started development on is Spine 3.8, so we plan to keep it that way for a while.
If there is a strong demand, we will consider v4, but for now, we have no plans to do so because our priority is the Android version.
As for DragonBones, we do not support it.
If the json after Spine conversion works, I think it will work.
(I think those can be seen in the demo version)