A charge a day keeps a dying battery away
Battery Plus is a free app from Gtechnology. It allows you to save on battery life by cleaning up apps that are running and using it in the background. It also monitors how your battery is being used, and takes steps to make its usage more efficient. It also tracks your battery as it charges, preventing it from losing capacity over time by making charges more efficient. It is a little unreliable, though, and may not work for every user.