The privilege of being first to market with any tech means you're the only choice for people who want what you're offering. Exogear's iPhone 4 battery case is in this lucky position. The good news? It's actually well done.
The Exolife provides great battery life extension while keeping the overall size only slightly bulkier than a bare iPhone. It also prevents you from touching the antennas—great for those who live in low-signal areas. However, as much protection as there is for the back and sides of the phone, the screen and surrounding bezel are practically naked.
How it works
The main point of the product is that it's a battery for your iPhone. Exolife comes in black or white models and has a 1500mAh battery to complement the 1420mAh battery inside the iPhone 4. This equates out to double your phone's lifespan, or in human-use terms, an extra day of regular iPhoning before you even start using the internal power.
Your power switch, headphone jack, volume buttons and camera are all exposed through the plastic shell, but the volume, mute and power are harder to get to because they're slightly obscured by the case. Not impossible, but more annoying.
The biggest functionality drawback is the fact that there's no passthrough 30-pin connector to dock your phone to an iPod dock or iPod-compatible alarm clock, meaning that you'll have to remove and reassemble the case every day if that's part of your routine. Disassembly is also slightly tricky if you don't get the hang of pressing hard on the latch release mechanism. If you don't use iPod docks, you can still sync your phone to iTunes by using the on-board miniUSB port and a miniUSB cable, which does a pass-through to your 30-pin iPod connector. This is also the way you charge the Exolife battery.
As for the Exolife as a phone protection device, it's good if you never drop your phone on its face. The way it's built, your front glass is actually raised up higher than the case itself, meaning it offers zero protection for a flat drop and will have your screen take the brunt of the impact. If Exogear had only made the sides slightly raised, like the Apple official bumper casing, there would be nothing to complain about.
Until other companies like Mophie and the rest of the pack that made iPhone 3GS batteries release their iPhone 4 line, Exolife is the way to go. We're all pretty lucky that the first-to-market is so good. [Exogear]
1500mAh battery doubles your iPhone use time
Sturdy build, thin and light
Has miniUSB pass-through for iTunes syncing, so you don't have to take out the phone every time
Slightly hard to disassemble
Good protection for the back and sides, but zero for the front