What makes it a tricorder is that it takes a drop of your blood and tells you your blood glucose level.
Blood glucose readings tell you more than a number - it informs what is happening - just like a tricorder. How much insulin do I take, do I eat or take a walk? Do I go to bed or march around the house for half an hour?
So cool - I have a tricorder. There are a lot of people here wearing Google Glass - is anyone else thinking Geordie LaForge from Next Generation?