Having a backup battery pack to recharge your iPhone can be a real lifesaver. But what happens when the backup needs to be recharged? And you're nowhere near a power source — like, at the beach, or in the woods, or on a mountain?
Well, if the sun is shining, you're in luck. iThrough is now offering an external battery pack with a built-in solar cell (US$20.99) for the iPhone 4. Once you've charged it normally (which takes about 4.5 hours), the pack is ready to come to your iPhone's rescue with a respectable 2400 mAh of reserve power. The solar cell can also be used to recharge the battery when you're nowhere near a wall outlet or car charger, and will trickle-charge the battery from any strong light source. (We didn't test how long it took to fully charge the pack just via the cell; just bear in mind that it won't be instantaneous…)
The pack includes a charge-level indicator on the non-solar-cell side. Unlike some other bottom-mounted batteries we've tested, using your iPhone to make calls or web-surf while the pack is attached is a piece of cake. Like of most of the iThrough products we've looked at recently, the price drops if you buy in quantity, and airmail shipping is free.
Check out our hands-on review below: