Starling Home Hub firmware 14.3 and above support Google's new garage door open/close detection capability for supported cameras. If you are signed up for Google Home Public Preview, have a 2021 model Nest Cam (wired) or 2021 model Nest Cam (battery) connected to mains power, and your camera is pointed at your garage door, Starling Home Hub will add a sensor to HomeKit for your camera to indicate whether the garage door is opened or closed. You can use this sensor to check your garage door open/close state from the Apple Home overview screen, or to trigger automations.
Enabling garage door detection in Google Home
In the Google Home app, navigate to your camera's live view, press '...' top right, Settings, Events, Seen events. Under Event history, make sure Garage door is enabled.
For more information on setting up garage door detection, see Google's support article. After enabling in the Google Home app, you will need to restart Starling Home Hub by going to the Starling iOS app, Help and Troubleshooting, Restart Hub. After restarting, wait a minute or so for Starling Home Hub to resync with HomeKit before proceeding to the next section.
Setting up in Apple Home
In the Apple Home app, navigate to your camera's live view, press the 'gears' icon at the top, Accessories, then touch the Garage Door State tile to bring up its settings page. Touch Display As, then select Garage Door.
The garage door open/close state will now be shown alongside the other sensor tiles for the camera.
You can now see at-a-glance if your garage door is open, as this will be indicated in the status strip at the top of the 'Home' view in Apple Home. You can also create automations that trigger if your garage door is opened or closed.