I just finished a seven-day biking and camping trip. I wanted to bring my Apple iPhone along to take pictures, take notes, and stay in touch as needed. But the battery on my iPhone would last for only one day.
My solution was a New Trent iCruiser IMP1000 11000mAh External Battery Pack and Charger battery pack. According to the specifications, this battery pack would hold enough charge to recharge my iPhone six times–perfect for this trip. At a cost of around $80 through Amazon.com, it seemed worth the investment since I could also use it for future camping trips or travels overseas.
The battery pack has an on switch with a LED indicator but no audible cues. The iPhone, fortunately, announces when it begins charging, so it’s easy to tell the battery is working. The battery shuts itself off when the phone is fully charged, so there is no need to worry about whether it’s on or off. The only way to tell when the battery runs out of charge, however, seems to be to plug the iPhone into it and see whether it works. Mine did run out because I charged another device on it, and I was left one day without iPhone usage as a result. A full battery recharge takes several hours. It comes with a couple of additional adapters and will work with anything that you can recharge in a USB port as well. It weighs about a pound and packs easily.