"Siri, turn on the Lights." That's a command you can say to the new HomeKit connected Hue lights that arrive later this month. Hue lights are WiFi connected LED lights that allow users to change the color, brightness and turn them on or off from the iPhone.
Hue Lights are not new, but the ability to control them with Siri is new. You'll need to buy the new HomeKit compatible version or if you can't wait you'll need to buy an upgraded Hue HomeKit bridge.
Hue Starter Kit $199 at Amazon