The geeks at MS and Purdue found that advertisments pushed to your phone can cause up to 70% of you battery usage. I wonder since this is Googles claim to profits, will they dump a bag of money in long lasting battery research? If you root, make sure you use ad-blocker.
Quote:
"A team of researchers from Purdue University and Microsoft has discovered that up to 75 percent of app-related battery drain in Android can be caused by ad-serving processes."
"In testing Angry Birds, Pathak recorded energy usage for one level of gameplay, and found that less than 30 percent of the app's battery drain was caused by the game itself. The other 70 percent was consumed by the uploading of user information metrics, location, and downloading and displaying of adverts."
http://www.theverge.com/2012/3/19/2884902/android-apps-battery-efficiency-study