FastMac's iV iPhone charger or battery pack that is available in the market now, which has a 3100mAh capacity, a USB port, a flashlight and the ability to actually dock into standard iPhone ports.
FastMac's iV iPhone would be best back-up for the iPhone 3G mobile phone.due to all the its features. Its 3100mAh battery can charge the phone about five times from 20% capacity to 80% capacity, and in absolute terms, it's the most amount of juice in any backup battery iPhone case out there now. The USB port, at the bottom, allows you to charge an extra device on the road (maybe your Bluetooth headset) at the same time as the iPhone.
