Spigen’s Style Ring ($25) is an interesting little add-on for your iPhone. Style Ring is a rotating aluminum ring attached to a small plastic piece which attaches to the back of an iPhone. The ring can be worn on one’s finger to prevent dropping the iPhone during use, and Spigen points out that using the ring to hold the phone can allow you to access more of the screen during one-handed use. The ring, which can be moved and turned in all…