The Sena Argyle has got be the most amazing and elegant looking pouch for the iPhone 4. It combines italian leather and embroidered argyle pattern for a very sophisticated look, not to mention it's a big attention grabber. Typically with pouch style cases you cannot have any other case on your iPhone 4 in order for it to fit into the Argyle. The Argyle has a very snug tight fit which is a very secure so your iPhone 4 will not slide out by itself. You can however use a back skin and a screen protector on your iPhone 4 with the Argyle without any problems. At first the Argyle has a very tight fit and requires you to push a but hard to insert your iPhone 4 inside. After a week or so of daily use, the Argyle will break-in a bit to completely form fit the shape of the iPhone 4 which will make it easier to fit.