Mophie Juice Pack Air iPhone case

A rechargeable battery integrated into a protective case, Mophie's Juice Pack Air is claimed to be the world's thinnest Apple-certified external battery for the iPhone 3G and iPhone 3GS.

The main drawcard of the Mophie Juice Pack Air is the fact that it offers the convenience of extended battery life for your mobile phone and the protection of a hard case in one device. A built-in power switch allows you to turn the battery on and off, so you can use the Juice Pack Air as a regular case and simply flick the switch when your iPhone requires a recharge.

Mophie claims the Juice Pack Air is the world's thinnest device of its type. Although that’s a feat in itself, the Juice Pack Air is still rather chunky and adds considerable bulk to your iPhone. We love the convenience that this accessory offers, but many users will be turned away due to the bulk and weight that the Juice Pack Air adds to the normally sleek and stylish iPhone. We like the rounded edges, though, and the glossy smooth finish feels very nice. It attracts plenty of fingerprints, just like the iPhone itself.

The Mophie Juice Pack air protects most of the iPhone's body, particularly the bottom of the phone. However, it leaves the top of the chrome edging exposed, so if the phone falls flat on its front the edge may be scratched or chipped. The top of the Juice Pack Air also feels a little flimsy when it's removed. It fits the phone quite tightly.

The battery in the Mophie Juice Pack Air is rated at 1200mAh, and according to Mophie provides an extra 4.5 hours of talk time and up to 270 hours standby time for the iPhone 3G and iPhone 3GS. Using an iPhone 3GS, we switched on the Mophie Juice Pack air battery when our iPhone battery reached 10 per cent, and it charged our 32GB iPhone 3GS to 70 per cent capacity before it was fully drained. Alternatively, you can leave the Juice Pack Air switched on even when your iPhone is fully charged; its battery will completely drain before the iPhone's battery is hit.

LED status indicator lights on the back of the Mophie Juice Pack Air allow you to quickly check how much battery is left by pressing a small button. The LEDs also indicate the charging status when the Juice Pack Air is switched on, and the recharging progress when the case is plugged in.

The Mophie Juice Pack Air uses a standard micro-USB connection for recharging. Conveniently, you can charge and synchronise your iPhone with iTunes without removing it from the case. Mophie includes a standard micro-USB cable in the sales package and the case is available in black, white and purple.

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