One of the apps that I installed on my new phone is Carat
Carat is a research project that aims to detect energy bugs—app behavior that is consuming energy unnecessarily—using data collected from a community of mobile devices. After running Carat for about a week, you will start to receive personalized recommendations for improving your battery life. We are based out of the AMP Lab in the EECS Department at UC Berkeley, collaborating with the University of Helsinki
If you are running Carat or decide to install it leave a comment with your device, OS and J-score I am interested to see how different devices stack up.