This seems like a rather useful concept device, especially if you want to give free diving a try, but are worried that something bad will happen. The Deepdive is a 2-piece set, containing 2 wristwatches, one for the free diver, and one for the control diver. What is useful about this setup is that the one on the free diver will be relaying information to the other watch, so if the free diver should suffer from hypoxia and suddenly faint, the control diver will know what’s going on, and can go save the day. There isn’t much information on how this will all work, but it seems that the chip inside the device requires nanotechnology in order to work, so maybe we won’t be seeing this become a reality so soon. If you were to take up free diving, would you invest some of your hard-earned money on this?