Anyone got a charger? If you're tearing your hair out at your phone running out of juice all the time, it could be that your favorite apps are to blame. New research suggests that up to 75 percent of free Android apps' battery use is spent on advertisements and other hidden tasks.

New Scientist reports the findings from Indiana's Purdue University, where curious boffins built special software to analyze apps' power demands.

For example, the research reveals (PDF) that smash hit Angry Birds, among others, spends just a fifth of the power it uses on actually playing the fowl-flinging game. Instead, nearly half of the energy used by the app goes toward checking where you are using GPS and downloading adverts over 3G that are specific to your location.

Read more of "Free Android apps waste 75 per cent of power on adverts" at Crave UK.