very cool - I wonder if a more generalized smart cap for prescription drugs could track usage in the same manner.
But asthma is pretty unique since the inhalers are used in "rescue" situations and there are strong geographic correlations that arise from environmental issues.
I would think this approach would work well if applied to other diseases where the frequency that the patient takes the medication is tied to symptoms - chest pain/nitroglycerin or acid-reflux/antacids are a couple of examples.