Amazon calculates a product’s star ratings based on a machine learned model instead of a raw data average. The model takes into account factors including the age of a rating, whether the ratings are from verified purchasers, and factors that establish reviewer trustworthiness.
I bought a Padfone and did the online search to see what keyboard/case I could use with it, and this one was recommended. The Padfone is thicker that a normal iPad, so it doesn't stay held in as well. It's ok for now. But that jazzed all in all.