Mophie has been making cases for the iPhone since the smartphone launched years ago. The thing that the cases all share is an internal battery that allows the smartphone to run longer between charges. Most iPhone users will tell you that a case with a battery in it is important if you use the internet or play games a lot.

The juice pack case on the market right now will fit the AT&T iPhone 4, but not the Verizon version. This is thanks to the slightly lower controls on the right side of the smartphone. Mophie has announced that a new version of the juice pack air will land in March that will work for both of the iPhone 4 versions.

The case has a 1500mAh battery inside and can double the runtime of the iPhone 4. The first case will be black with silver accents, making it look very much like the iPhone with no case on. Later will come a glossy white version and a red version for those wanting a change. The iPhone can be charged and synced with the case installed using an included cable. The case will sell for $79.95.