The Google Home app is available for download in the Google Play Store (for Android mobile phones and tablets). It offers another avenue to mirroring to a TV or display, requiring only a valid Gmail account and a Wi-Fi connection to cast your phone or tablet’s screen. The process to setting up your Google Home app consists of a brief and fairly simple wizard; once you have selected your Gmail account and allowed the app to access your location, you will arrive at the app’s home page.
From here, you will want to expand the vertical menu by pressing the menu icon (seen circled in red in the image below):
Once the vertical menu has expanded, you need to press the menu option, “Cast screen/audio”.
Once you have a Chromecast TV set up on your wireless network, you should see the device come up once you’ve pressed the CAST SCREEN / AUDIO button (see the image below).
If you have any issues getting your device to connect, or if you have some other issue with the Google Home app we recommend you contact Google support at https://support.google.com/chromecast/answer/6373887