mophie has unveiled the 7th generation of its juice pack line, promising on-the-go power for Apple's latest iPhone 4 via what's billed as a light-weight and ultra-thin external rechargeable battery case.

While Apple has improved battery life significantly with the latest iPhone, the new juice pack air virtually doubles the battery life of the iPhone 4 according to mophie.

The case design acts as a virtual speaker box, redirecting sound from the bottom of the iPhone 4 to the front, offering a richer, fuller sound quality, while the embedded electronics promises no signal interference with the iPhone 4. Its soft touch hardware also provides protection from bumps and marks.

Additionally, mophie's juice pack air offers up to an additional 6 hours on 3G, up to 12 hours on 2G, of talk time, up to an additional 36 hours of audio playback and up to an additional 9 hours video playback.
 
An integrated LED status indicator tells users exactly how much juice is left and also displays how much time remains during the charging process, which uses 500 milliamps fast charge technology, with what mophie calls an advanced battery for added safety, as well as 1500 mAh capacity.

mophie juice pack air

"mophie’s passion is creating intelligent products that help Apple fans interact with their device in new ways," said Ross Howe, Vice President of Business Development at mophie in a press release.

"With the release of the next generation form factor, it is only natural that we provide its users the extended battery life and protection that Apple fans have come to expect from mophie."

The new slimline mophie juice pack air costs $79.95 (around £52), more details can be found at www.mophie.com.

Notably, mophie produced the first-ever 'Works with iPhone' Apple approved battery case.