Charging an iPhone 4 through USB takes 30 minutes longer than using a wall charger
If you happen to find yourself in a rush to get out of the door as soon as possible and want to make sure you have a full battery on hand with your iPhone 4, you might want to charge it via the included wall charger. Apparently it takes an average of 23 percent longer to charge it through a USB port on a computer or some sort as opposed to using a wall charger. In the real world, this means that you'll be spending an additional 30 minutes waiting for your handset to top up to the max through a USB port instead of tethering it to your wall outlet. Unless time is something that's precious to you, it probably shouldn't bug you too much – but as with most other devices, the fastest way to completely charge your handset is probably through an outlet.
Apple iPhone 4 Specifications | Review
via MobileCrunch
Apple iPhone 4 Specifications | Review
via MobileCrunch
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