Before the app can collect reviews for your store, you need to enable the Google Customer Reviews add-on in your Google Merchant Center account and sign the program agreement. This is a one-time step.
How to enable the add-on
Sign in to your Google Merchant Center account.
Go to Settings (the gear icon).
Select Add-ons.
Find the Google Customer Reviews add-on card under the Discover tab.
Click Add.
The add-on will now appear under the Your Add-ons tab. Click Go to Google Customer Reviews.
Review the program agreement and click Sign agreement.
Once you've signed the agreement, Google Customer Reviews is enabled on your account.
Claiming your website
Make sure your store's website URL has been claimed in your Google Merchant Center account. The domain must match your Shopify store's primary domain exactly, including whether or not it starts with www.
You can check and update your claimed website under Settings > Business info in Google Merchant Center.
What about the opt-in integration step?
Google's setup process includes an "Opt-in integration" step where they ask you to add code to your website. You can skip this step, our app handles the integration for you.
Simply install and configure the Easy Google Customer Reviews app, and it will take care of delivering the survey opt-in to your customers.
Next steps
Once the add-on is enabled, head back to the Easy Google Customer Reviews app in your Shopify admin to continue setup. You'll need your Merchant Center ID to proceed.
For more information on the Google Customer Reviews program, see Google's official documentation: Google Customer Reviews basics.