https://apps.shopify.com/product-reviews-addon
It's the addon we never had and wished that the Product Reviews app comes with.
It helps to automate your review process, you'll be able to schedule the emails to send to customers after X days of their fulfillment or purchase date.
Best of all it lets the customers leave a review directly inside the email!
Installation is breeze, I just had to install both the Shopify's Product Reviews App and Product Reviews Addon App and you're done.