Even though a good chunk of the world is celebrating various holidays this week and next, the accessory market that revolves around Apple's smartphones shows no sign of slowing down. It continues to churn out example after example of new designs. Which, of course, means it's time for this week's iPhone-case roundup. Today's installment features old-style vinyl records, extreme sports, and the most destructive force in all of nature: children.

Amzer: The Flip Case (iPhone 4 and 4S; $15) provides a simple flip-case for your handset. Made of leather, it protects all sides of the iPhone while keeping its screen within easy reach at all times. Its magnetic clasp ensures that the case stays firmly closed while in use. The Flip Case is available in white and black.

Edge Design: The Alfa (iPhone 4 and 4S; $99) is a slick, lightweight aluminium case that takes its design and production cues from the racing cars of famed Italian team Alfa Romeo. It's available in anodized black, yellow, white, or blue, and comes with its own waterproof pouch.

Griffin Technology: Griffin has partnered with Third Man Records to manufacture the Third Man 45 Case (iPhone 4 and 4S; $30), which provides protection and nostalgia with its backing inspired by the 45 RPM vinyl records of old. In addition to the three base models (white, yellow, or black), the company also sells a separate set of three backings for $20.

KangaPouch: If you've ever seen a child play with an iPhone, you know what a joy it is to watch them—right up to the point where they accomplish the most childlike of objectives: destroy everything within a forty foot radius, including your precious smartphone. This is where the KangaPouch (iPhone 4 and 4S; $40) comes into play. Currently being funded through a Kickstarter project, the case is designed to counteract the devastation that only a toddler (and possibly a Category-4 hurricane) is capable of unleashing. The case's rubber design, reinforced hinges, grip bars, and completely enclosed construction will keep those tiny hands at bay. It also includes a kickstand, and it can cover the iPhone's Home button to keep the youngest users from exploring other apps. The KangaPouch will be available in green, orange, and blue.

i.Fuzen: The HP-1 (iPhone 4 and 4S; £70) has it all: In addition to being a case, it features an amplifier that boosts audio quality and power for more-demanding headphones, while its built-in battery provides backup power for your handset. And, of course, it comes with plenty of protection thanks to its hard-shell construction. The HP-1 is available in black or white.

iSkin: The Lil Keeper (all iPhone models; $70), part of the company's Ducati Collection, offers excellent padding—think sanitarium wall—and plenty of fashion sense for carrying your phone or similarly-sized device. The Lil Keeper features a secure zipper, a carrying strap, and a carabiner for securing your iPhone to a backpack or handbag. The case comes in white, black, or red.

Speaking of backpacks and Ducati, the Sling (all iPhone models, $220) is a front pack designed to sling across the front of your body when riding a bike. Among its many amenities is a pocket designed specifically for a device the size of an iPhone.

Noreve: The Tradition (iPhone 4 and 4S; $56) features a flipcover held fast by a magnetic clasp, as well as two pockets that can hold cash or credit cards. The usual cutouts ensure that all the handset's ports, buttons, and cameras remain accessible, while the soft-padded leather construction provides plenty of protection and style.

Optrix: The Optrix HD (iPhone 4 and 4S; $90) is a super-protective case designed for users who combine an active lifestyle with a love of moviemaking. The case is water-resistant, can be mounted on a variety of surfaces by means of a vibration-dampening sled, and provides superior shock absorption.