All Google Home and Google Nest devices let you make free phone calls over Wi-Fi, but the Google Nest Hub extends this to Google Duo video calling too. By recognising your voice it is clever enough to ensure it calls only your contacts, and not those of another member of the household. (Control who can make calls on Google Home.)
One thing to note is that while you can call anyone in your contacts library, you cannot place calls to emergency services over Google Home.
You may have configured Google Duo during the Nest Hub setup process, but not to worry if you didn't. All this stuff is easily accessible within the Google Home app, as we'll outline below.
It's worth pointing out that there's no camera on the smaller Nest Hub, so your recipient will not be able to see a video feed of you when placing a video call over Google Duo. However, you'll be able to see them, and pure audio calls still work just fine.
Link a Google Duo account to Google Assistant
To set up Google Duo video calling, launch the Google Home app and select Settings. Scroll down to Google Assistant Services and choose More settings, then select the Services tab and choose Voice & Video calls. Choose Video & Voice Apps.
Select Google Duo to link an account. You may be asked to enter a phone number if you are not already using Google Duo, and may have to enter a verification code sent via text message.
If you have multiple Google Home devices you will now see them listed below. Toggle on any devices on which you want to be able to make Google Duo calls over Wi-Fi.
The process can be a bit confusing, but if you've missed anything important then Google Assistant will prompt you to fix it when you make your first video call.
Make a phone call over Google Home
Having configured your settings the next part is really easy: just tell Google what you want it to do.
The fastest way to make a phone call is to simply say "Okay Google, call [person's name]", but on Google Nest Hub you can also ask it to "Make a phone call" and it will display onscreen a list of contacts from which you can physically scroll through and select a contact.
To use Duo rather than a standard audio call, in our testing we found we had to specifically say "Okay Google, call [person's name] on Duo."
When you've finished your phone call say "Okay Google, hang up."
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