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 analyses reviews to verify trustworthiness.
The normal version can't make circles This one makes great circles. The designs don't seem to erase as good as the old one did. Even after a very thorough shake, the old design can still be slightly seen. It is usable though.