In the past, we've reviewed a lot of external iPhone batteries, and we've reviewed a lot of iPhone cases both hard and soft. The main problem is that one is often incompatible with the other: the batteries often plug into the iPhone's synch jack, but with even a soft bumper case installed, that extra few millimeters of rubber may keep the battery plug from seating properly. And do you really want to struggle with removing ANY kind of case just to give your iPhone a little boost of energy?
PowerSkin doesn't think so. Their answer is to merge a silicone case and external battery into one package. We took a look at their iPhone model, but PowerCases are also available for a variety of HTC, Samsung, and MotoDroid phones, with prices in the US$49.99 to US$59.99 range.
The iPhone PowerSkin (which fits both AT&T and Verizon models, by the bye) starts with a super-slim 2000 mAh battery which, with the docking plug and mini-USB charging/sync jack, provides a stiff framework onto which the silicone case is molded. Installation consists of plugging your iPhone into the docking plug and pulling two case corners into place — not much harder than a regular bumper case. Depending on usage, you can expect an additional 4.5 to 8 hours of life from your phone; a row of status LED's on the bottom tell you immediately how much juice is left. (The case is also smart enough to charge your phone's battery first, then charge its own…)
Check out our hands-on review below: