Although Mophie isn't the first to have an iPhone 5 battery case, there's no doubt that some have been waiting for the company's take -- and it might justify the patience. The just-launched Juice Pack Helium slides a 1,500mAh secondary battery on to the back of Apple's flagship in a protective frame that's 13 percent thinner than earlier Mophie cases, but still promises a hefty amount of extra runtime. Mophie estimates another six hours of cellular calling and data (seven on WiFi), or about enough to push through an all-nighter or a long airport layover. Color-coordinating black and silver versions of the Helium are shipping from the 14th onwards for about $80. That's lot for something so model-specific, but it's possibly the sleekest way to extend an iPhone 5's charge.