Unlike the Learning Thermostat, Nest sells Nest Protect in two colors: white is currently sold in multiple stores, while black is exclusively available through Nest’s web site. The white version we tested wasn’t Apple-style pure white, but rather a tone that blends into the off-white paints typically used on home ceilings. Each Protect has one circular central button with a multicolored, swirling ring of light hidden within a recessed edge, as…