Nest has introduced Nest Protect ($129), a smoke and carbon monoxide alarm. Like the company’s earlier Nest Thermostat, the alarm can be controlled using an iOS app. Nest Protect is able give an early warning to smoke or let users know when carbon monoxide levels are rising by lighting up yellow and speaking with a human voice.
Nuisance alarms can be canceled out by waving an arm near Nest Protect, rather than touching a physical button. Nest Protect can also send a message to any smartphone or tablet as soon as the alarm goes off, as well as monitoring its own battery levels and sensors.

Nest Protect alarms can work in conjunction with each other, communicating even if Wi-Fi is down.
The alarm also works in conjunction with the Nest Thermostat — for instance, the alarm automatically turns off a gas furnace if the carbon monoxide alarm goes off. Also notable is the Protect’s Pathlight feature, which can illuminate a dark hallway when triggered by motion. Nest Protect comes in black and white, and is available now for preorder.