Over the last couple of days I've run CNET's tablet battery drain test on both the new iPad and the iPad 2. The iPad 2's battery life hadn't been tested since iOS 4.3, so while my focus was on evaluating the new iPad's battery, this was also an opportunity to see if iOS 5.1 brought any battery life improvements over 4.3.
The results speak for themselves, but if you need further explanation, continue reading after the chart.
|iPad (2012)||iPad 2 (iOS 5.1)||iPad 2 (iOS 4.3)||Transformer Prime||Transformer Prime w/keyboard dock|
|Movie battery life (in hours)||12.8||14.2||11.9||9.6||15.3|
How we tested battery life
We evaluated battery life the same way we do for all tablets: by continually running a movie file on the iPad until its battery dies.
We set each tablet to Airplane mode and adjusted its respective brightnesses to 150 candelas per square meter (cd/m2) or as close to that number as possible. For each iPad, that's a bit lower than the halfway mark on the brightness scale.
We ran the 720p iPad version of "Toy Story 3." On the Transformer Prime, we ran a 720p version of "Toy Story 3." The new iPad also supports 1080p playback of movies, but we've yet to run the battery test with a movie file at that resolution.
On the iPads, we ran the movie through the Videos app; for the Prime, we used the movie player app mVideoPlayer, as it provides a much-needed repeat video function that not all native Android movie players include.
While the new iPad drained faster than the iPad 2, its 12.8 hours of battery life is still the second-highest result we've seen on a tablet using a single battery. Even compared with the Transformer Prime with its battery-embedded keyboard, the iPad lasted only 3 hours less. Even more impressive was that it achieved this running at that incredibly impressive 2,048x1,536-pixel resolution.
Looking at the iPad 2 results, we also saw evidence that Apple made some very meaningful battery optimizations going from version 4.3 to 5.1 of its OS. And although the iPad 2 got 1.4 hours more juice when watching a movie, nearly 13 hours of continuous 720p playback is nothing to thumb your nose at. That gets you an entire season of "Game of Thrones," with enough leftover power to squeeze in a couple "The Walking Dead" episodes as well. That's a lot of good-looking entertainment you can consume on just one charge.
We will follow up soon with more iPad battery life results, including Wi-Fi-, 4G, and 1080p tests. Also, check out our fullfor more comparisons.