When the battery of your iPhone dies and you do not have access to electricity, for example, if you are fishing or in the mountains you can use this solar charger, it converts sunlight into electricity. The charger has an indication, which can monitor the charge level of the battery. When you have power you can use it as a simple battery with the included USB cable.
Solar charger for iPhone 4S/4
video Solar charger for iPhone 4S/4
Solar charger for iPhone 4S/4 (ID: D42)