The ExoLife has several features that should make iPhone 4 owners clamor for it -- a 1500-mAh Lithium-ion polymer battery that should be able to recharge the phone once, a hard polycarbonate shell to keep your baby from getting scratched and dented, a regular USB 2.0 to micro-USB cable for charging and syncing, and something called ExoClear technology to help you avoid the dreaded Grip of Death.
The ExoLife also has a feature to turn off the battery when it's not being used, as well as a thin blue LED battery meter on the back. As you can see in the photo above, the case is relatively sleek as battery cases go, and looks pretty nice to me, although your personal preference may vary, of course.
Exogear plans on having the black model seen above shipping by July 30th, and a white model will follow by September 30th. The ExoLife will be perfect for running TrailGuru on my iPhone 4 when I'm doing long hikes or bike rides, so I'll be anxious to see one soon.