I found this article today on NewScientist.
Abhinav Pathak, a computer scientist at Purdue University, Indiana, and colleagues made the discovery after developing software to analyse apps' energy usage. When they looked at popular apps such as Angry Birds, Free Chess and NYTimes they found that only 10 to 30 per cent of the energy was spent powering the app's core function.
Free apps eat up your phone battery just sending ads - tech - 18 March 2012 - New Scientist
Abhinav Pathak, a computer scientist at Purdue University, Indiana, and colleagues made the discovery after developing software to analyse apps' energy usage. When they looked at popular apps such as Angry Birds, Free Chess and NYTimes they found that only 10 to 30 per cent of the energy was spent powering the app's core function.
Free apps eat up your phone battery just sending ads - tech - 18 March 2012 - New Scientist