I believe i have read somewhere that you don't need task killer it hurts your battery more constantly running in the background scanning for apps the battery life is mainly from your screen so get a brightness widget then also get Juice Defender and Juice Plotter
Juice Defender - Being online at any time and any place is what smartphones are all about. But this continuous connectivity comes with a pretty annoying drawback: high power consumption, hence short battery life.
JuiceDefender extends your battery life by intelligently and transparently managing the most power-draining components of your Android device, like 3G/4G connectivity and WiFi.
It is ready to go right after installation: the preset modes are the perfect way to easily gain precious hours of battery life - literally as easy as one tap!
And if you want to go under the hood, you can tweak everything to your unique needs, because JuiceDefender is also fully customizable through a clean and intuitive user interface.
Once configured, JuiceDefender runs by itself improving your battery life in a fully automated manner.
Information gathered from
JuiceDefender - Battery Saver | Battery manager app for Android
JuicePlotter - JuicePlotter is a battery usage graph that combines full at-a-glance information about your battery consumption with sheer beauty.
The coloured bands along the graph show screen brightness, radio usage, charging status and battery temperature. Just scroll around to find precise information and make sense of the different colours.
The Analysis mode will let you easily have an idea of how your battery is performing, showing the overall estimated battery life for each day and overlaying the previous days on the graph for easy comparison of relative performance.
The best feature is probably the Home screen widget that shows an accurate estimate of how long it will take to fully discharge/recharge your battery
Everything about this app is free
Information gathered from
JuicePlotter - Latedroid | awesome apps
Hope this helped
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