iPhone Battery
The iPhone uses a lot of battery and therefore has installed a
battery-saving measure: After 40 seconds without using it will
dim down, then switch off automatically. If you are looking for
the battery you will discover that the iPhone is closed and sealed,
you can not open the device to remove the battery or replace it.
Apple store offers many battery app's for free that can tell you
the status of your battery and the amount of time left for various
functions as game play, talk time, 3G internet etc.
I recommend on "Battery Magic".

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