The main feature Mophie improved with the Juice Pack Air is the size of the embedded lithium battery. While the Helium comes packed with a 1500 mAh batery, the Air comes with a larger 1700 mAh battery. This is the difference of being able to fully charge the iPhone 5 to 100 percent with the new Air, or bring the iPhone 5 up to an 80 percent charge with the Helium.

So what do you give up to gain so much more battery life? Size. The Juice Pack Air’s dimensions are 2.60 x 5.54 x 0.63 inches and it weighs 2.68 ounces, compared to the Helium’s dimensions which are 2.49 x 5.49 x 0.59 inches at a weight of 2.44 ounces. It does not seem like much, but every little bit matters when you are trying to wrap your hands around the longer screen of the iPhone 5.

The one feature that is still missing from both the Air and the Helium when comapred to other Mophie battery pack cases, is the ability to sync via the attached cable. The Mophie Juicepack Air for the iPhone 4/4S will allow you to both charge and sync via the cable. It’s a feature that may be important to you if you still tether your iPhone to offload photos or sync to your music library on your computer.  Mophie claims that both the Juice Pack Helium and Air cases for the iPhone 5 will only allow you to sync wirelessly when charging, hardly a feature of the case, mind you.

The Juice Pack Air will cost you $99.95 compared to the Helium’s price tag of $79.95. The other main difference that the Air has compared to the Helium is color. The black version of the Mophie Juice Pack Air is available now and will ship in seven to 10 days. If, on the other hand, you are interested in either the red or white version, you will just have to wait until March 22.

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Tech 21 Impact Band $39.99

This minimalistic design provides basic bumper protection on the sides as well as a clear plastic back to protect the finish from scratches. The soft D3O® material fits snuggly around the phone and protects the edges from drops and adds color (nine choices) and personalization to your iPhone without adding bulk. This is a great case for people who don’t generally like cases.

X-Doria Dash $34.99

Want protection but don’t want anyone to mistake your iPhone 5 for any other product, like the iPhone 4? The Dash provides side and back with hard plastic protection for your iPhone while leaving a clear window to show off the distinctive iPhone 5 logo and coloring. Currently available only in black, it’s a slight step up in protection without much compromise

Scosche Kickback $29.99

The kickBACK is a thicker hard plastic protector for your iPhone 5 with a sporty finish that makes the phone easy to grip even with sweaty hands. The case comes in five different colors as well as basic black and white.

The cool feature of this case is the integrated kickstand which makes FaceTime easy as well as movie viewing in landscape mode. Clever.

Gumdrop Drop Tech $44.95

Although the more traditional extreme case manufacturers such as Otterbox were not able to provide samples in time for this review, Gumdrop actually sent me a case for review the day of the iPhone 5 launch. This case provide complete integrated protection for all ports as well as the screen in a dual-layer design of hard plastic skeleton enveloped with a soft plastic exterior with stylized tire-inspired texturing. Currently only available in black, more colors are on the way

This is a slightly bulky product, but if you need hard core protection, this is a great case.

As far as how these manufacturers developed cases so quickly, basically they guessed. ”We made some assumptions to be in a position to move very quickly once specs are unveiled by Apple,” tech21 CEO Jason Roberts said in a statement.

Because this iPhone is made out of aluminum, it’s supposed to be less likely to crack or shatter. Are you going to get a case for your iPhone 5 or go “naked”?

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