Does your MIDI controller keyboard send program change messages but lacks a numeric display showing the program number sent? If you use that controller to switch sounds during a live performance, you would certainly like to know what program you have selected. But without a display, you might be out of luck. Heres the solution: Use your iPhone or iPad as your display. This app makes it possible. It listens for the program change message sent by your keyboard and shows the value when received. Supports split screen and slide over view on newer iPad models.