When the screen has been in sleep mode for a few minutes, Wi-Fi and data traffic will be disabled and most applications will be inactive to save battery life.

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It's designed to tell when you're actually looking at your screen, keeping its sleep mode from kicking in when you are and shutting down to save battery life when you're not.

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This start-up allows users to save battery power by keeping the power turned off when the camcorder is not in use, while making sure that unexpected shooting opportunities are not lost.

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Then I went to John Fogerty and The Blue Ridge Rangers before turning off the phone to save my battery for the 911 call.

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"We're achieving a very significant amount of battery savings, " said Microsoft's principal programme manager Ruston Panabaker, who would not be drawn on exactly how much overall battery life Windows 7 will save.

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The Battery Engineer is a great way to help the environment and save a great deal of money on reduced battery purchases.

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Battery life is about six hours and the battery is in the hinge of the device to save space.

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Starting at the back, the removable battery cover has a matte, almost soft-touch finish, save for a plastic section surrounding the camera lens and LED flash.

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