The overall rating reflects the current state of the app. It accounts for all app reviews but prioritizes the most recent ones.
To be completely honest, this app does EXACTLY whats it's meant to do about 98% of the time and it's great for just that. Have scaled over 100k with this and it has worked fine, no pay pal headaches. This app could be developed further to make it more consistent however, i recommend it for the price!!