The FuelBand doesn't track stairs climbed, as the other two do, but it translates any activity that involves wrist movement (walking, dancing, directing traffic) into a metric it calls NikeFuel.

WSJ: Keeping Fit, One Step at a Time

The bracelets displayed at SIGGRAPH 2007 each contain an accelerometer that senses wrist movement and a Bluetooth module for wireless communication, which not only makes it possible to interact with other wearable's but also laptops and mobile phones.

CNN: You wear IT well

From the first footsteps on Swiss soil you notice it - in the wheels of the airport luggage carts, in the baggage carousels, in the tailoring of the porters' jackets, and in the movement of the wrist-watches advertised all around.

BBC: Swiss movement

The idea being that a pin and roller style music box is inserted into the movement of a traditional mechanical wrist watch.

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Are these new techno-driven wrist bracelets a path to liberation, or more like the ankle bracelets that enable law enforcement to monitor the movement of prisoners under house arrest.

FORBES: My Not Yet Quantified Self

The quartz movement does not require battery changes, as a rotor in the watch moves with the motion of your wrist to charge the internal battery.

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