Study says free Android apps can zap your battery life

Study says free Android apps can zap your battery life
You might think that there is no cost for installing a free app on your Android device. But according to a new study done by Purdue University and Microsoft, while you personally are not paying for a free Android app, your battery is paying with its life. The study took a look at several Android apps including Rovio's Angry Birds and The New York Times app. What was discovered was that as much as 75% of the energy used to run a free app is spent running third party ads that help defray the cost of the app. The New York Times app used a lot of energy even after all the news (which we assume was 'fit to print') was loaded on the screen.

As a result of the study, it might be suggested that those who are saving money by opting for the free versions of an app could be losing in battery life what they are saving in payments. The study used a tool called an eprof to determine that most apps spend the majority of the time performing I/O functions such as accessing a 3G or Wi-Fi data. Most apps have a "tail" which can keep a handset running full-power even when the app is loaded. For example, with Angry Birds, 45% of the power used to run the app is for the third-party Flurry ad network. Of that 45%, 15% is used by the GPS on your phone to confirm your location and 24% belonged to the 3G "tail".

An Android user can use a lot of energy just opening a search page in the native browser. The GPS and 3G requirements for such an act would add up to 16% and 31% respectively of the total 2,000uAh of battery life burned. Do you ever browse CNN on your mobile device? That will cost you 2,400uAh in power, mostly for data as there is no need to find your location.

To show you how much energy is used after an app loads, a sample app was devised by the guys behind the study and connected with a remote server. 5 packets of data was sent which used 127uAh of energy. After the app loaded, it ran for another 6 seconds, burning 187uAh in energy for a total of 57% of the energy used. That "tail" also happened to occur if the routine was delayed by 5 seconds after the connection was made. This extra use of energy also shows up when a bug called a
"wakelock" tricks the device into running at a high-power state and keeps it running at that level. The study found that such bugs were in Android's Mail program and the Facebook app.

Despite the theory that ad servers were responsible for the vast majority of energy use to run a free app, that most of the energy used to run applications are used for I/O operations. The conclusion of the study was that further research is needed to optimize the use of battery life when running Android apps.

source: PCMag



1. parkwaydr

Posts: 572; Member since: Sep 07, 2011

I would believe this, if the study wasn't conducted by Microsoft, who would have an obvious reason to be slanted and biased, with a possible touch of over exaggeration.

4. TKFox007

Posts: 303; Member since: Nov 02, 2010

I totally agree with you Microsoft has been running their mouths lately with little to no proof of their claims and doing publicity stunts that they tipped in their favor.

26. cellgeek82

Posts: 518; Member since: Dec 20, 2009

That's because Microsoft is wetting their pants from Apple and Android domination. The only thing keeping people smiling at Microsoft is Xbox. In my opinion is the best thing they've ever made. Aside of that I can't stand Windows. I'll take Apple OS or Android over PC.

27. parkwaydr

Posts: 572; Member since: Sep 07, 2011

I agree, xbox is awesome, I think windows made a huge mistake with metro UI, I have a lot of friends that are die hard pc guys, and they have flat out said that if ms puts metro UI on Windows 8 they will go to mac.

2. windowsRocks

Posts: 155; Member since: Oct 28, 2011

I dont think IPhone is an exception for this.

3. Android2627

Posts: 28; Member since: Mar 03, 2012

Hey You Have Android Phone as ur Pro Pic and ur profile name is Windows Rock and u write about iPhone Wired!

5. CM_Punk

Posts: 173; Member since: Mar 13, 2012

I don't think the iPhone has anything to do with this.

8. windowsRocks

Posts: 155; Member since: Oct 28, 2011

Miz is Back

12. Whateverman

Posts: 3295; Member since: May 17, 2009

"I don't think the iPhone has anything to do with this." Has that ever stopped any article from turning to that discussion before? Unfortunately not.

33. CM_Punk

Posts: 173; Member since: Mar 13, 2012

Stopped me from doing what?

34. remixfa

Posts: 14605; Member since: Dec 19, 2008

miz, i think the point was that free-ad supported apps drain extra battery. the iphone or even WP7 apps will be no different by the very nature of how ad support works.

35. CM_Punk

Posts: 173; Member since: Mar 13, 2012

You can't even get my name right, so how would you know what the point is? #bestintheworld

15. Lucas777

Posts: 2137; Member since: Jan 06, 2011

no it is… this is one of the few benefits to ios multitasking.. it has little to no impact on battery life… which for some people might be a huge advantage… personally i like a mix of the two (for anyone who has an iphone and wants it just download backgrounder… then you can choose when to do android multitasking)

20. thelegend6657 unregistered

Backgrounder rapes my battery !

21. Whateverman

Posts: 3295; Member since: May 17, 2009

And is ios multitasking really multitasking? It does what it does well, but it only works for certain apps, not all.

28. SleepingOz unregistered

nopes, ios "multitasking" 's real name is multithreading.

31. nnaatthhaannx2

Posts: 820; Member since: Oct 19, 2011

multitasking has nothing do to with ads and gps. try again.

32. Lucas777

Posts: 2137; Member since: Jan 06, 2011

ya but putting it straight into the background to run is the same-- still uses the ads and gps

7. frydaexiii

Posts: 1476; Member since: Dec 01, 2011

Hmm, all thanks to those freemiums like those games from GLU which always has push notifications on for ads. I swear it's so annoying to have to keep killing the task, I would rather just pay a fixed price and have them leave me alone...

9. sprockkets

Posts: 1612; Member since: Jan 16, 2012

In a completely unrelated story, all apple apps are paid apps, never display iAds and never, ever, ask for your location history. All apple devices clearly show what has been using the battery, and so does WP7. Also, all android phones prohibit turning off the GPS, 3G or wireless functions, which are very well hidden in the power widget.

10. Sinaps

Posts: 60; Member since: Jul 27, 2010

Did you get this from reddit? I read this article on reddit yesterday.

11. JGuinan007

Posts: 699; Member since: May 19, 2011

Um no at the bottom it tells you they got it from PCMag probly the same place reddit got it.

13. gallitoking

Posts: 4721; Member since: May 17, 2011

Nothing is free... Androids.... nothing... who cares who did the study it does make sense

16. frydaexiii

Posts: 1476; Member since: Dec 01, 2011

Denial at it's finest, of cause you feel that way, you probably already spent hundreds of dollars on apps at the Apps store that we could get free on the Play Store. To me it doesn't really matter about battery life, since my battery, even with what the research says on free apps, still last about 13-14 hrs a day...

14. VJo003

Posts: 365; Member since: Mar 11, 2012

I guess the difference between apps for money & apps for free is that apps for free actually cost more !!!!

17. pongkie

Posts: 663; Member since: Aug 20, 2011

nice try MS, Nice try

18. mercorp

Posts: 1045; Member since: Jan 28, 2012

well,a way to overcome this and these ads is to switch off packet data and wifi.saves battery life.

19. djg71087

Posts: 70; Member since: Oct 10, 2010

of course to buy something is always the answer!

22. darktranquillity

Posts: 285; Member since: Feb 28, 2012

The police in the country is good for nothing, they arrested me twice. Once for beating up my wife and another for selling drugs.

23. saiki4116

Posts: 413; Member since: Mar 31, 2011

"wakelock" isn't a bug.It's what devs use to keep phone awake mostly for games...

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