I have 3 mobile phones that I have carried in the past year, an iPhone 4, a Samsung Focus, and a Samsung Galaxy S2 (ATT).  There are things about each of them that I like and dislike but the biggest selling point for me is battery life.  Recently I decided to do some testing of these phones to see which one has the best battery life.  To do this I came up with a simple script that represents some real world use of these phones.  I wanted to get an idea of battery life with only 2-3 hours of testing on each phone so the script uses the phone extensively and notes that current battery level at predetermined points.

The script is as follows:

  • Load 10 predetermined websites (the same websites were used for every phone).  We will load each website 5 times each.
  • Watch a YouTube video at least 30 min in length (same video used for all phones)
  • Listen to a playlist of music that is stored on the phone.  Music is played at max volume through the attached speaker.  Playlist was allowed to play for 30 minutes and the same playlist was used by all phones.
  • Make 10 phone calls, each 1 minute in length.  The calls used the speakerphone with the phone placed face up on the desk.  The same number was called for each of the 10 calls.
  • Play video game for 10 minutes (vary by phone)
  • Take 10 pictures at the highest resolution in common on all phones
  • Take a 20 minute video at 720p resolution
  • Use the GPS to navigate a short road trip.  The trip was just a few miles and we used the same trip for all phones.  Note that we were not doing turn by turn as some of the phones doesn’t support that natively.  During this trip we will be bluetooth streaming some music to our truck radio.
  • And our last test is to load each of the 10 websites we used in test #1 twice using our 3G connection (non-wifi)
Before we give the results, it’s important to note a few things about the phones:
  • The iPhone 4 is approx 14 month old so it’s reasonable to believe that it’s battery life would be degrated somewhat.
  • The Samsung Galaxy S2 is running a custom ROM so it’s numbers might be somewhat different than stock though it’s believed that stock might be slightly worse.
  • The websites we used for the first test are listed below the table
  • The YouTube video we used was a GOP debate.  We used that video because it was 1h 40m long.  The url is http://www.youtube.com/watch?v=UBRxb07PPWA
  • The playlist was a collection of our personal music.
  • All phones had WIFI enabled and connected to the same access point.  All phones had GPS and bluetooth enabled and were set to maximum brightness with auto brightness disabled.
  • We attempted to test each phone from the same location (our desk) but since we were testing with active sim cards in them and the tests were taking at least 1 hour, some random events did occur which we have noted.
  • Each phone had a single GMail account enabled and set to push emails to our phone
  • Every attempt was made to stop any additional background tasks from running during testing
  • Our Windows Phone 7 phone had their Facebook and twitter accounts removed and the other phones had apps like Facebook removed 
  • The game played on the iPhone was Temple Run.  The games played on the Samsung Focus were Shuffleboard and Angry Birds.  The game played on the Galaxy was Angry Birds.
And now the results in table form.  Note that the battery percentage listed in each column is the battery percentage the phone reports after running the test.
Test iPhone 4 Focus Galaxy S2
 Load 10 websites 96% 96% 97%
YouTube video 88%  85%  90%
 Music playlist 84% 79%  87%
Make 10 phone calls 78%  73%  83%
Play game 73%  68% 78%
Take 10 pictures 71%  67%  77%
Shoot 20 min of video 58%  54% 66%
GPS trip 50% 43%  58%
Non-wifi Page Loading 45%  36%  54%
The websites we used for our web loading test are full desktop versions of the home pages for the following sites.
  • Yahoo
  • Slate
  • CNN
  • Microsoft
  • New York Times
  • ESPN
  • Oracle home page
  • Fox Sports
  • Slashdot
  • Fox News
This study is pretty unscientific but every effort was made to treat the phones fairly and get an accurate read on battery life on each device.  Due to the age of some of the devices,  your results may vary.  Drop me a line with any comments.