The overall rating reflects the current state of the app. It accounts for all app reviews but prioritizes the most recent ones.
No Stars is what it should get. Absolutely useless app. Any store using similar standard product mockups is flagged as a potential breach. Reviewing and marking just a handful of the 1757 "hits" wasted 15 minutes of my time. Then I realised that whatever algorithm they are using, doesn't work. Please investigate and remove it from App store. This product should not be pulling private product images and store data when it appears to be fundamentally defective.