Compatibility: iPhone 1st Generation, iPhone 3G (8GB, 16GB), iPhone 3GS (16GB, 32GB) Capacity: 2000mAh – Doubles battery life of iPhone 3G 3GS Charge and sync iPhone 3G 3GS with iTunes without removing it from the O2 device. Technology: Smart battery technology drains battery of the O2 device first before switching to the iPhone’s battery Convenient [...]