PROBLEM: Many car chargers will not work when a bumper is fitted to your iPhone 4, even ones that say they are compatible with the iPhone 4. As you probably don't want to remove the bumper everytime you get in your car you need a solution that allows you to leave the bumper fitted and charge your iPhone whilst in the car.
SOLUTION: Buy a car charger that has a female USB hole in it. Here is an example:
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| The Griffin PowerJolt Car Charger for iPad, iPhone and iPod |
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| The Griffin PowerJolt Car Charger for iPad, iPhone and iPod |
The Griffin PowerJolt Car Charger for iPad, iPhone and iPod
IMPORTANT BIT: Then, instead of using the black USB/iPhone cable that comes with it, just use a standard white apple USB power lead.
It works fine for me. Give it a try.
