Video of System
I've had plenty of physical therapy over the years and Naveen's comments really struck a chord (she designed her app after trying to perform her own PT exercises from a sheet of paper). Often you see a therapist after surgery; you're in pain, probably not in a particularly attentive mood, and I know I generally felt worse when I left than when I arrived! That's invariably when the chipper therapist hands over a badly photocopied piece of paper with poorly worded directions! Making a video of your exercises and then using an app to track reps is a great idea, as is the capability of discovering which exercises are most effective for each condition, gender, age, etc.