The overall rating reflects the current state of the app. It accounts for all app reviews but prioritizes the most recent ones.
The Shops at Mount Vernon
This is one of the best reccomended product apps on Shopify. It's a one-click installation and it's ready to go. The app learns from your product catalog and customer purchases. Best of all it has a dashboard of statistics that show you how well it's working. I would highly recommend it for your store.