Stage is an application designed to run in conjunction with the main EigenD application which allows for the control of parameters within EigenD using 'widgets' on a number of graphical canvases, or 'Tabs'. Stage can be running alongside EigenD on the same computer, or in future releases on a different computer on a network or even on an iPhone or iPod touch, allowing many possibilities for control whilst performing with the Eigenharp.
You can find out more about the Stage application here: