Up to 75 per cent of the energy used by free versions of Android
apps is spent serving up ads or tracking and uploading user data:
running just one app could drain your battery in around 90
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.
For example, in Angry Birds only 20 per cent is used to display
and run the game, while 45 per cent is spent finding and uploading
the user’s location with GPS then downloading location-appropriate
ads over a 3G connection.
I’ll bet it’s true for ad-based iOS apps too. Another reason to pay for apps rather than settle for free ones.