Having ratings and reviews on your site are great! Adding markup for them is even better as they can lead to a Google Rich Result. (You can learn more about this here: https://developers.google.com/search/docs/data-types/review-snippet)
Here is a run down of the different review apps, that we currently integrate with via our plugins. You will see our product markup pull in the aggregate rating information from these apps.
- Yotpo (paid version)
- Shopify Reviews
- WooCommerce Reviews
- BigCommerce Reviews