I don’t like the corporate weight that his being thrown into wearables as it has the potential to steer the positive energy of Quantified Self into a race for buying gadgets. When people feel they are improving their lives because they have five or six gadgets in their inventory then we are simply perpetuate the perceptual error fitness clubs exploit where membership is a proxy for feeling less guilty for being out of shape.
For me Quantified Self is about self awareness. Logging and being aware of the way our bodies and minds work changes our behavior and improves our lives. In my own experience the act of logging itself is the exercise because moving my awareness to the behavior changes the behavior.
It is not the device on your wrist or sewn into your coat seams, it is about your attention. Where it resides in real time, consistently over the course of your life. And that has nothing to do with how many gadgets you bought.