This isn't the first time we've seen a Booqpad product from Booq, but Booqpad for iPad Air ($60) shows that the company continues to improve on its designs. The case has always been about pairing a tablet holder with a notepad, but this time, the case is a removable hard plastic shell, rather than a simple fabric frame. It fits onto the nubuck and polyurethane folio using strong magnets, and can be set up with the included paper on the left or right,…