Solar Cell Phone Chargers for your iPhone. 

Sunlinq USB Solar chargers are specfically designed to charge USB Devices through it USB ports at 5 Volts which is just what your iPhone needs.  The Sunlinq USB Mini 400 mAmp 5V Solar Panel Charger at full charing power will charge your iPhones battery in about 3-4 hours and the Sunlinq USB Plus 800 mAmp 5V Solar Panel Charger will charge your iPhone in less than 2 hours.  The Sunlinq USB Solar Chargers are some of the best on the market and provide reliable power from the sun.  The Wagan Solar Battery Charger also works great to charge your iPhone.  Charge the internal AA rechargeable batteries then use the device to charge your iPhone.