To calculate the overall star rating and percentage breakdown by star, we don’t use a simple average. Instead, our system considers things like how recent a review is and if the reviewer bought the item on Amazon. It also analyzes reviews to verify trustworthiness.
We use these in conjunction with a Cell Phone Lanyard Strap when we are using our boat. Now we don't have to worry if we accidentally drop an iPhone XR overboard as these provide adequate buoyancy for the heavier phones.