Apple accessory company mStation Mophie has given the iPhone 3G an extra lease on life. The company's Juice Pack Air is a rechargeable 1,200 mAH lithium-ion external battery that doubles the amount of talk time from 5 hours to 9.5 hours.

The Juice Pack Air, which promises to be the thinnest battery extender yet for the iPhone, will cost $79.95 and features a standby mode to switch between the standard and additional battery life. It'll be available in black, white, and purple.

Mobile users can keep an eye on the four LED lights on the external extended battery as well as the indicators on the iPhone.

The unit should be available this spring at Apple retail stores and at mophie.com.