OtterBox launches the Black/Yellow and Black/Blue style of its Commuter Series case for iPhone 4. The Commuter case has a multi-player design featuring a self-adhering screen film keeps the multitouch display screen free of scratches, then a silicone jacket wraps around the device to absorb shock and provide grip while a thin yet strong polycarbonate shell rounds out the protective layers and helps the device slide easily in and out of a pocket or purse.

Mophie updates its Juice Pack Plus battery case, offering compatibility with all iPhone 4s, …

Third Rail Mobility introduces its Third Rail System battery case for smartphones that includes the Slim power-ready protective case and Smart Battery universal, interchangeable, removable battery. Unlike other smartphone battery cases, Third Rail’s system provides several different usage modes in one simple system – functioning as a protective case, a power case, a portable external charger and a power hub for charging multiple devices at one time.

Hipstamatic introduces its HipstaCase 100 kit designed to turn your iPhone 4 into a 80s retro style camera. The HipstaCase is an one piece, snap on case that protects your iPhone 4 while bring the look of plastic cameras from the 80s to iPhone 4. The kit also includes a tripod adapter that slips into a hidden front slot on the case and easily mounts onto any standard camera tripod, and a wrist lanyard designed to seamlessly attach to the HipstaCase in either a left or right handed position.

Seidio introduces the CONVERT, a smartphone case with a unique 2-in-1 case design, ideal for users in industries such as EMS, trucking, automotive, insurance, or outdoor enthusiasts who want to switch between rugged and sleek device protection, to suit any environment.

Here is a new dual-SIM case for iPhone 4 that supports dual standby and doubles as a power pack. After you attach the battery case to your iPhone 4, you will have two SIM card slots – the original Micro SIM slot of the iPhone 4 and a mini SIM slot on the case. Compare to another dual SIM case, the new case supports dual standby, meaning both SIMs are active at the same time.

Chinese company HiSense introduces a range of WHDI (Wireless Home Digital Interface) accessories, including a WHDI Transmitter Stick, a WHDI Receiver and a WHDI case for iPhone. The WHDI technology allows users to connect HD source such as notebooks, tablets, iPhone to HDTV wirelessly.

Speck launches the CandyShell Card iPhone 4 case that not only protects your iPhone, but also offers the ability to securely hold up to three cards (ID or credit cards) plus some cash in its built-in rubberized slot. It is “the case to carry when you don’t want to be weighed down with a bulky wallet or a heavy purse.”

A company called MountMe introduces the Freedom, an all-in-one iPad carrying and mounting device. Basically, the Freedom is a protective case for iPad that easily transforms into a highly adaptable and practical mounting device.

Following the iPad case, iChair bring the iPhone 4 case with dual compatibility fitting both AT&T and Verizon iPhone 4. One of the main features of iChair’s case is its integrated adjustable kickstand designed for media watching in  portrait and landscape modes.