If you haven’t done that already, these steps walk you through that process.
Turn on the TV and plug the Chromecast dongle into the HDMI port on the TV.
Download and set up the Google Home app on your iPhone or iPad.

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In the Google Home app tap theDevicestab and then tapAdd.
ChooseGoogle Nest or partner machine.
Choose a home in which to place the Chromecast.

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Wait while the Home app looks for your Chromecast, and then pressYes.
If it doesn’t find it, selectChromecast / Google TVfrom the list and ensure it’s plugged in.
Read through the terms in the next two steps.

PressAcceptand thenI agreeto get through them.
Select where in your house the Chromecast is located.
If necessary, follow any other final steps you see in the Google Home app.

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fire up the app you want to cast from.
Netflix, YouTube, and many other apps work with Chromecast.
Tap your Chromecast from the list.
To stop casting, tap the samecastbutton and then chooseThis gadget.
To do this, you’ll use AirPlay and a computer running Chrome.
Install a casting receiver app on your iPhone or iPad.
You’ll have to do this because AirPlay won’t connect to Chromecast.
Open Chrome’s menu and go toCast, save, and share>Cast.
ClickSources>Cast screen, and then choose your Chromecast.
To mirror the mobile gear, initiate the AirPlay receiver youve downloaded.
On the iPad or iPhone,initiate the Control Centerand tapScreen Mirroring.
Tap the AirPlay receiver.
This will cause a problem when watching a video or listening to audio.