All Google Home devices let you make free phone calls over Wi-Fi, but the new Google Home 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 Home 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 Home 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.
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Link a phone number to Google Assistant
For simple audio calls you need not use Google Duo at all, but you will need to link your phone number in the Google Assistant settings.
Launch the Google Home app and tap on the account icon at the bottom right, then choose Settings. Select the Services tab, then Voice & Video calls.
For non-Duo calls select the top option for Mobile calling.
Click Edit below Your own number, then choose to Add or change phone number.
You'll be prompted to enter your number, then a verification code will be sent over SMS. If your phone doesn't pick this up automatically then enter the code.
Link a Google Duo account to Google Assistant
To set up Google Duo as well as mobile calling, head to the same menu in the Google Home app via Settings > Services > Voice & Video calls. This time select Video & Voice Apps.
Select Google Duo to link an account. You'll be asked to enter your phone number, then click Add.
Once again a verification code will be sent to your phone that should be entered here if it does not pick it up automatically.
You should also go to the settings menu for your smart display and enable Duo video calling here. Launch the Home app, tap the Smart display icon, tap the Settings cog, then scroll down to Duo and enable it.
The process is honestly 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 Home 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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