I bought a Mophie Juice Pack in Philly last week while in town speaking at the Middle States conference. My relatively new iPhone 4S was struggling with lasting even a three-quarter day while on the road. The case itself is a little bulky, but it saved my bacon everyday over the weekend in Tampa. I’m not sure it is a daily case, but when on the road it is a must have.
I had the first Mophie (for 3Gs) and it was lifesaver for long flights, even if it bulks the phone up. Does it get more than a charge from it? Some of the smaller battery packs (ones about 2x iPhones thick) I have seen now have enough for several charges.
Of course the one I got for my 4s and all of my other accessories are rendered doorstops with the new 5 connector.
Some things to reduce battery suckage are, if you can, turn off wifi (cause it keeps looking for networks), turn off GPS, turn off notifications. I did this last time I walked a marathon, and got almost 6.5 hours life out of the phone with a mophie like pack.
It only really gets one full charge, but that seems to be enough to get me through a heavy use day with some life still there come late night. When I am on the road I turn off wifi, but the one thing I use constantly is the location services for tagging photos and posts. I also have a small external battery pack but now with the Mophie I can’t easily plug it into the 30 pin on my 4s. Not sure what I will do when it is time to jump to the lightning connector. I guess just pony up!