Xperia ZL also includes Battery STAMINA Mode that significantly improves the battery standby time by automatically shutting down battery-draining apps whenever the screen is off and starting them up again when the screen is back on.

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In addition, the Ascend W1's 1950mAh battery provides the longest standby time of smartphones in its class.

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Its battery life: 5 hours on the wireless web. 30 days of standby time.

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Also included in the package are a charger, an antenna and a 1500 mAh NiMH battery that promises up to two hours of talk or 36 hours of standby time.

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The Cord Free uses a AA battery that is sufficient to give it 25 hours of talk time and three months of standby power.

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The technology also provides long battery life (over 10 hours2 of local HD video playback) and over 3 weeks of standby time.

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