Adding the arre Temperature Sensor to HomeKit is super easy. Open the Home app, scan the Matter QR code on the device or in the manual, and follow the prompts to assign the sensor to a room.

The Apple Watch Series 8 and Apple Watch Ultra feature a new temperature sensor. Here's how it works and what you can use it for.

The new watch includes a new temperature sensor — two of them, in fact. There’s one temperature sensor on the back crystal near your skin. And another just under the display.