Android controlling arduino over bluetooth using Firmata Firmware

Im working on a project that involves controlling several parameters of a system based on the inputs. The inputs will be taken from analogIn and parameters are to be controlled using digital/analogWrite. I have used firmata in the past and interfaced it with my laptop using processing in which i made a GUI.

Now i want to port my processing thing to an android phone using a bluetooth transreciever. I have heard about apps which uses the same idea.But i want to edit the GUI to display custom details.

Can anyone provide me leads on the same?

Regards,

Rohit

Has anybody tried it before?