Drag lock (to lock desktop widgets) adds itself to that menu. I don't remember if it's a modified hildon-desktop or separate binary that edited the menu. Find it and I can take a look at how it works.

Do you use telescope or stock app menu? Does the app switcher key next to screen open the stock app menu? You could launch the app, if it has one, without touching screen. Unless you have telescope, it can't launch apps without touching screen.

Telescope does however allow the fullscreen and zoom/volume buttons to be bound to commands when the app switch button has been pressed. But first you'd have to figure out how to launch the status bar applet's window from a command. Same applies to launching it from app menu, unless it already has an app in there.