Many smart light bulbs... well, aren't. You can control them, but they're often blissfully unaware of what's going on in your home. Stack aims to change that with its recently unveiled Alba bulb. This sensor-packed illuminator changes brightness and color based on the time of day, location and who's present in the room. It'll start with cooler, more natural white hues when you're just waking up, but will switch to relaxing warm colors when it's late. It will also dim or shut off the lights when there's a lot of ambient light, or if you've left for work; alternately, it will come to life when there's a big commotion. There's a mobile app if you need to tweak settings, but the goal is to avoid using it as much as possible. Much like a Nest thermostat, Alba will learn appropriate behavior and (hopefully) let you keep your phone in your pocket.