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Battery Life: What To Expect

The Complete iPad 3 Review: Retina Display, A5X, 4G LTE, And Camera
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Enhanced image quality and correspondingly higher power draw requires a larger battery. Apple’s solution for the iPad 3 is a whopping 42.5 Wh Li-ion battery, representing a substantial change from iPad 2’s battery rated at 25 Wh. This larger battery explains the iPad 3’s added heft, but also helps explain how Apple is able to claim comparable battery life as the iPad 2, even in light of a device that incurs increased power consumption. The Retina display and GPU are both both notable energy hogs, but the 70%-larger battery pack compensates for the greater power demand.


In addition to contributing weight, a larger battery pack requires much longer to reach a full charge. At least five hours is necessary to hit 90% capacity.

Fully charging the iPad 3 takes as long as six hours (about 33% longer than both the iPad and iPad 2). That's the longest recharge time measurement that we've ever recorded, but not too bad given the iPad 3's 70%-larger battery pack.

Although you'll spend longer recharging Apple's new iPad, real-world use validates the company's claims of comparable battery life. At maximum brightness, the iPad 3 delivers about six hours of Web browsing, putting it at the top of our chart.

In the interest of full disclosure, our benchmark involves surfing sites like CNN and Wikipedia. While we also play MP3s in the background during the benchmark, we've discovered that workload really has no impact on battery life because ARM's NEON SIMD engine is incredibly efficient at decoding music files.

In previous tablet reviews, we standardized on a maximum brightness setting, neglecting to normalize display brightness. This wasn't an accidental oversight. There's a legitimate argument to be made in that most people set the highest value on their notebooks and tablets, dimming it only if they get a low-battery warning.

With that said, normalizing screen brightness to 200 nits enables a fair apples-to-apples tablet display comparison. In that environment, the iPad 3's battery life jumps to more than nine hours, a four-hour increase from the max brightness setting. Asus' Tegra 3-powered Transformer Prime comparatively gains less battery life from our standardization, enjoying about one hour extra hour of battery life with its display set to 200 nits.

Apple's latest tablet falls a bit shorter in movie playback. While the iPad 2 delivers more than half of a day's worth of battery life, the iPad 3 trails at 11 hours, roughly on par with the Transformer Prime.

Epic Citadel on iPad 3Epic Citadel on iPad 3

Measuring battery life while gaming is tricky business on tablets. Unlike desktop/notebook PCs, there aren't any solid synthetics able to cross platform boundaries to facilitate comparisons between devices. Further, the wide variety of available games impose different CPU/GPU loads. One of the more popular titles for iOS is Epic's Citadel because it's based on the same code used in Infinity Blade. Much like 3DMark, Citadel loops a sequence through the app's landscape. But while it delivers a decent level of graphical detail, we're not quite sure if Citadel is an ideal test because it's the same scene over and over.

Suspiciously, when we first started benchmarking the iPad 3, it consistently delivered the same battery life as Apple's iPad 2. Fortunately, we have other options for validating our results.

Riptide GP on iPad 3Riptide GP on iPad 3

Originally ported from Xbox Live to Android, Riptide GP is now also available for iOS. This is a more appropriate title for benchmarking because it's an actual game. Riptide is also capable of serving as a reliable benchmark because it automatically enters into a demo mode when it idles on the home screen. According to the developer (Vector), the textures are dynamically rendered during the demo, causing the system to be continuously stressed. Our benchmark results show this happening as well.

The iPad 3's quad-core SGX543 GPU and Retina display requires much more power than the iPad 2 that came before. Yet, Apple's new iPad still manages to serve up about five hours of battery life while gaming, which is close to the original iPad.

Display all 51 comments.
Top Comments
  • 13 Hide
    aicom , April 16, 2012 6:46 AM
    Tomfreaklol FAIL hard when I see keyboard are displayed on TV as well despite being docked and to make thigns worst one still need to carry the adapter around to plug HDMI......

    +1 to the keyboard thing. But remember that most tablets (all?) don't have full size HDMI so you probably need a dongle 99% of the time anyway.
  • 11 Hide
    confish21 , April 16, 2012 5:46 AM
    its cool if I lick my finger for page turning right?
  • 11 Hide
    alchemy69 , April 16, 2012 11:05 AM
    "Typically, you're looking at a tablet from less than a foot away"

    Really?
Other Comments
  • -6 Hide
    tomfreak , April 16, 2012 5:24 AM
    lol FAIL hard when I see keyboard are displayed on TV as well despite being docked and to make thigns worst one still need to carry the adapter around to plug HDMI......
  • 4 Hide
    confish21 , April 16, 2012 5:38 AM
    Really a solid tablet. Just wish the adapter and outrageous bills could disappear... Great Review!

    100 degrees is damn hot but I think the results are justified.
  • 11 Hide
    confish21 , April 16, 2012 5:46 AM
    its cool if I lick my finger for page turning right?
  • 6 Hide
    hardcore_gamer , April 16, 2012 6:08 AM
    I'm waiting for an x86- Windows 8 tablet.
  • 13 Hide
    aicom , April 16, 2012 6:46 AM
    Tomfreaklol FAIL hard when I see keyboard are displayed on TV as well despite being docked and to make thigns worst one still need to carry the adapter around to plug HDMI......

    +1 to the keyboard thing. But remember that most tablets (all?) don't have full size HDMI so you probably need a dongle 99% of the time anyway.
  • 2 Hide
    tomfreak , April 16, 2012 7:13 AM
    HDMI port is not very thick, I still wonder whats keeping them from putting in on tablet.
  • -1 Hide
    Maziar , April 16, 2012 8:20 AM
    Great article! very detailed.
  • 1 Hide
    aicom , April 16, 2012 8:25 AM
    TomfreakHDMI port is not very thick, I still wonder whats keeping them from putting in on tablet.

    The port isn't all that's needed. There's also a bit of hardware around it for the socket that makes it a tad thicker and a stretch to fit in the chasis of tablets.
  • 11 Hide
    alchemy69 , April 16, 2012 11:05 AM
    "Typically, you're looking at a tablet from less than a foot away"

    Really?
  • 2 Hide
    tomfreak , April 16, 2012 11:37 AM
    aicomThe port isn't all that's needed. There's also a bit of hardware around it for the socket that makes it a tad thicker and a stretch to fit in the chasis of tablets.
    looks like we gonna wait wide adoption for mini display port for TV then.
  • 3 Hide
    bustapr , April 16, 2012 11:45 AM
    more than 5hrs to charge. thats not to my liking. the transformer prime was the only battery life vs charge time tablet I saw.
  • 1 Hide
    Augray37 , April 16, 2012 1:05 PM
    The display is 9.7", not 10.1".
  • 3 Hide
    cknobman , April 16, 2012 1:17 PM
    Alchemy69"Typically, you're looking at a tablet from less than a foot away"Really?


    Yeah I thought that comment was bunk too. Typically I use my tablet 1-2 feet away as less that 1 foot away would have the thing shoved up in my face too much and not give me any arm reach to operate the device properly.

    As for the display in the iPad3 I went to the apple store and looked at it side by side with the iPad2. The colors look great but the super high pixel density was not as big of a difference as these reviews made it out to be.

    The biggest things I noticed when comparing iPad2 and 3 side by side was the increased thickness and weight. Those 2 factors were enough for me to want to choose the iPad2, especially if I could get it a little cheaper than the iPad 3.
  • 1 Hide
    mcd023 , April 16, 2012 2:01 PM
    I am curious, was it just a reduction in pixel size that made the higher gamut? that doesn't really make sense to me. Does anyone have more info?
  • -3 Hide
    nycnut , April 16, 2012 2:10 PM
    The data plan graphic is WRONG! Verizon offers 2GB vs ATTs 3GB for the same $30. Check your facts...
  • 1 Hide
    hoofhearted , April 16, 2012 2:53 PM
    I am not a fanboy of either camp. I have a tf prime and just got the ipad 3. I just wish apple would put a friggin sd slot. Watching my dvd collection while at the gym on the eliptical machine is a must and I am not fond of jumping though hoops to swap content in and out.

    I also am curious about who will get the gaming win (more depends on where the devs go):
    android tegra3, ipad3, vita, 3ds, or maybe microsoft will pull a rabbit out of their hat with win8.

  • -5 Hide
    badtaylorx , April 16, 2012 3:00 PM
    damn....i dont come here for apple news.....
  • 0 Hide
    jamesjones_det , April 16, 2012 3:15 PM
    I'm not supporting and/or dissing the iPad or Tom's hardware but technically there is a "wireless" option with AirPlay and an Apple TV or Mac.

    I'm just saying if we are supposed to be a technology site we should be sure the facts are correct.
  • 1 Hide
    CaedenV , April 16, 2012 3:52 PM
    give me a 16:9 or 16:10 tablet capable running an independant 1080 or 1200 capable external display with a native miniHDMI connector for easy setup for presentations and video watching (does not need 3D support on external display). I also want removable storage for SD cards as an option, and a USB port or 2 if it is not too much to ask so I can hook up my video camera, or keyboard, or credit card swiper without dealing with a dock. Lastly, I want a minimum 128GB of internal storage on it for $300-400. I will take a slower processor, or lowered graphics for the sake of a minimum 128GB of storage. Lastly, I want full MS office to run on it, none of this web-based office365 junk, especially if I am going to be out and about and not wanting to waste my 4G plan just to run office.

    If I am going to pay $830 for a limited use tablet with 64GB storage and 4G, then I think I would rather spend that money on a notebook or ultrabook. I can still get a touch screen, I still get good graphics, I get a real keyboard/mouse, can still get a 4G option, and I get real x86 programs, removable storage, better connectivity options (USB3, thunderbolt), and (most importantly) real storage space.

    Also, I would prefer win8 over iOS, but iOS is not a deal breaker if they would come out with something that would fit my use.
  • 3 Hide
    acku , April 16, 2012 4:46 PM
    nycnutThe data plan graphic is WRONG! Verizon offers 2GB vs ATTs 3GB for the same $30. Check your facts...

    My fault. Corrected.

    Cheers,
    Andrew Ku
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