In the original PowerWatch by Matrix unique selling point was its ability to thrive solely on your body heat a thermodynamic generator, a tech that kept the wearable powered as long as you wearing it (and still alive).

But while it was refreshing to not have to worry about a draining battery, there was a lot wrong with the PowerWatch. Not only was the lacklustre design hard to love, but the only two fitness features worthy of using were step-counting and sleep tracking – both of which you could get with much cheaper, basic activity trackers.
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