We were hoping that someone would ask! Because the average person doesn't enter stage 2 of sleep until they have been napping for 25-30 minutes, they are relatively easy to wake up before then. So when Spark senses that the user is dozing off, the vibrations will be strong enough to wake the person back up.
The weight is 100 grams, slightly more than the average smart-watch. This gives it a legitimate feel of a real timepiece. The screen is full color LED 1.63 inches with 240x240 resolution.
The width is about 12mm. Overall, the watch should feel like a classic metal watch around your wrist with the exception of the silicon band.
Spark is, for the most part, water resistant. However, because of the open micro USB, it's not possible to make the watch completely water proof. You can definitely wash your hands or dishes with it, just don't go swimming.
There are many concerns in terms of health and risk to consider. Maybe it would be helpful, but it's not something that we can add without going through rigorous testing and health regulations, which would greatly delay shipment.
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