When I interviewed Tony Fadell, the inventor of the iPod and now CEO of Nest, two years ago, he told me that he started the company, which sells smart thermostats and alarms, because existing products for taking control of your home over the Internet were clunky and appealed only to the technically minded (see “Nest’s Control Freaks”). “Home automation is for single geeky guys. It’s not for families,” he said.