On a rainy New York morning earlier this week, a WIRED reporter strapped to his wrist a lavender and pink plastic child’s smartwatch and headed to work. As he approached his nearby subway station to commute to WIRED’s office, he texted Vangelis Stykas, the Greek security researcher who had shipped him the watch via Amazon, to let him know that he was going into the station and might lose cell signal.“I know,” Stykas wrote back.In fact, Stykas had been monitoring the reporter’s location via the w...