i personally don't care how symptoms are measured, but if there was a convienent and easy way that even doctors would find credible, then that would be great. imagine you want to provide "proof" that a supplement helps, that you are no longer taking meds and doing well, whatever. with this device or a smart phone you'd be able to do it, you could maybe just rent one temporarily.

and would be useful for elderly/patients having a difficult time expressing themselves, tells how much sleep you got, measure compliance - not sure how - and OC behavior - not sure how.