” The biggest problem with any smart phone is their low battery life. No matter how feature rich your cell phone is, its limited battery life could prove to be a big problem in some situations. Several apps for different platform are available for download which could save the battery life of your phone by turning off some unnecessary features and programs which are consuming the power of your phone. A similar app is available for Android users.”
Source : http://www.thegeekengineer.com/juice-defender-how-to-save-battery-of-your-android-phone/
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