Apple may not be exhibiting at CES this year, but it will still have remarkable reach thanks to HomeKit, a platform that lets companies develop smart-home gadgets that users can control with an iPhone or iPad. The introduction of HomeKit has sparked a race among innovators to create gadgets that can run on the platform. One of these, Withings, made a name for itself with wearables and other gadgets that promote health. This year it is branching out with Home, a smart HD camera and air-quality monitor that users can control from anywhere with an Apple device via HomeKit.