Battery Life

With the iPad Air Apple moved to a 32.4Wh battery, a significant decrease from the 42.5Wh unit in the 3rd and 4th generation iPads. The smaller battery doesn’t come with a change to Apple’s claim of 10 hours of battery life, which implies a reduction in overall platform power. I confirmed a substantial reduction in platform power in my crude measurements earlier in the article. Although it’s possible for the iPad Air to draw substantially more power than the iPad 4, our earlier power data seems to imply that it’s unlikely given the same exact workload. Our battery life tests agree.

We'll start with our 2013 smartphone/tablet web browsing battery life test. As always all displays are calibrated to 200 nits. The workload itself is hidden from OEMs to avoid any intentional gaming, but I've described it at a high level here.

Web Browsing Battery Life (WiFi)

Our web browsing workload came in at exactly 10 hours of continuous usage - an improvement compared to the iPad 4. Battery life on LTE was good as well, consistently delivering just under 10 hours of usage. The fact that both LTE and WiFi tests deliver similar results tells me that we may be bottlenecked by some other component in the system (perhaps display?).

I've been running the same video playback test for a while now, although we're quickly approaching a point where I'll need to move to a higher bitrate 1080p test. Here I'm playing a 4Mbps H.264 High Profile 720p rip I made of the Harry Potter 8 Blu-ray. The full movie plays through and is looped until the battery dies. Once again, the displays are calibrated to 200 nits:

Video Playback Battery Life (720p, 4Mbps HP H.264)

Video playback battery life also improves slightly compared to the iPad 4. Apple’s battery life claims aren’t usually based around video playback, so exceeding their 10 hour suggestion here shouldn’t come as a shock. Apple’s video decode power has always been extremely low.

Our final cross-platform battery life test is based on Kishonti's Egypt HD test. Here we have a loop of the Egypt HD benchmark, capped to 30 fps, running on all of the devices with their screens calibrated to 200 nits.

3D Battery Life - GLBenchmark 2.5.1

Our 3D battery life rundown test shows a substantial improvement in battery life over the iPad 4. IMG’s PowerVR G6430, running a moderate workload, can do so more efficiently than any of the previous generation GPUs in Apple’s SoCs. Much like the A7’s CPU cores however, there’s a wider dynamic range of power consumption with the G6430. Running at max performance I would expect to see greater GPU power consumption. The question then becomes what’s more likely? Since the majority of iOS games don’t target the A7 (and instead shoot for lower end hardware), I would expect you to see better battery life even while gaming on the iPad Air vs the iPad 3/4.

Charge Time

The iPad Air comes with the same 12W USB charger and Lightning cable that we first saw with the iPad 4. Having to only charge a 32.5W battery means that charge times are lower compared to the iPad 3 and 4:

Charge Time in Hours

A full charge takes a little over 4 hours to complete. The adapter delivers as much as 12W to the iPad, drawing a maximum of 13.5W at the wall. I still think the sweet spot is somewhere closer to 2.5 hours but that’s another balancing game that must be played between charge time and maintaining battery health. It’s still so much better than the ~6 hours of charge time for the iPad 3 and 5.69 hours for the iPad 4.

WiFi & LTE Connectivity Usability, iOS 7 and the Impact of 64-bit Applications
Comments Locked

444 Comments

View All Comments

  • superflex - Friday, November 1, 2013 - link

    You can cherry pick timeframes to make their stock look good.
    Over the last year, the stock is down 12%.
  • Janette - Saturday, November 2, 2013 - link

    @dsumanik: Yeah, what @John2k13 said.
  • whatsa - Sunday, November 3, 2013 - link

    John,
    you didn't do to bad yourself- lmao
  • peterfares - Monday, November 4, 2013 - link

    I'm sure if Apple implements NFC plenty of people will use it. So many people have Apple devices and you won't need to guess or remember if you can send things to each other. NFC is a bit of a mess right now. For contacts and URLs it's standard and should work between any device. But the big use case --files-- is a mess. On Android you basically can only send files between devices of the same manufacture. WP has file transfer standardized but it doesn't work with Android.

    Plus Apple users love to show people they have the latest Apple device and will love to beam things back and fourth.
  • Walkop - Tuesday, November 5, 2013 - link

    You accuse this guy of bias (which he obviously is, alongside being totally ignorant to one of the best tech reviewers out there (MKB does incredible videos). But you have no idea what you're saying yourself with some areas, and you very clearly have a bias towards the iPad.

    Touch ID is the more of a gimmick than Haptic Feedback. I've used it on the Nexus 10; it makes a BIG DIFFERENCE in the feel of the onscreen keyboard. NFC is very useful if you know others with Android devices; I've used it on various occasions. Wireless charging is extremely convenient, especially if its on your desk and you use your phone on-and-off.

    As for software; yes, the iPad hardware is considerably improved. But on the base level, the OS hasn't really been updated in years save for iOS7. That update added a lot of foward-facing changes, but not really too much functionality that hasn't been around already. iOS multitasking just got bumped up to be closer to Android, but still isn't nearly as flexible. Sharing is still difficult. You can't Bluetooth a group of PDFs to a friend (which I do weekly on my Android device), even!

    Gesture Type. I CANNOT give this up. I can't stand typing on an iPad because the keyboard experience is so sub-par compared to my Nexus 10, and it will only improve with KitKat where you can swipe through the spacebar to combine multiple words in a single gesture.

    You have apps, but so do Android tablets. There are many fantastic applications in every field that do their jobs admirably, and Google's set of tools are fantastic for writing, accessing information, sharing, and editing many formats of information. There aren't as many, but there are a lot of GOOD ones and even phone apps scale very well on a 10" display.

    And the Nexus 10 2013 will very likely bring the most powerful non-Apple SoC to the table: Snapdragon 800. It matches or beats the Apple A7 in many areas, although it is defeated in others. Simply put, it is a VERY competitive chip with the A7 and, really, they are basically equal.

    So please, stop bashing features that really DO matter to a lot of people, and I won't bash the iPad's lack of functionality (at a base level) when compared to Android devices out there. The iPad isn't the "perfect" device, neither is my Nexus 10. But we can't act like either is.
  • Brakken - Thursday, November 14, 2013 - link

    Love your response.

    So tiring having thoughtless and random posts!
  • ivan256 - Wednesday, October 30, 2013 - link

    That's a pretty uninspired list of proposed features.

    IMO, wireless charging is pointless. Is it really that hard to plug it in? How do you wireless charge while you're using it? It's added cost and size for trivial levels of added convenience.

    USB3 sync would be fine, if it actually sped things up. I'm sure they'll get around to it. Who doesn't wireless sync these days though?

    NFC would be another "me too" for a bandwaggon that is already slowing down. Really, think about the few places where NFC is catching on, and tell me you'd really use a 10" tablet in those situations. It would be almost as bad as the iPad-as-a-tourist-camera people.

    Here are some better ideas:

    Relaxing the iron fist - Let us install our own apps from outside the app store. If Apple wants to sign them first and charge a nominal fee so that they can "prevent piracy," so be it. But I want to install my own stuff. I want iOS to be able to participate in things like the Humble Bundle. I want more iOS OSS.

    Location Spoofing. Let us set location services to lie to apps temporarily. This is useful for a variety of reasons ranging from development to privacy.

    Home screen icon sizes. No further explanation needed.

    Put the good camera on the front. Nobody should be using the rear facing camera in most situations, but you want good low-light performance in FaceTime and Skype. If they could figure out how to center the camera in the middle of the screen through some optics magic, that would be incredible.

    Front facing speakers....

    Most of this boils down to just making the thing something I don't feel like I need to jailbreak. It's hard to improve a device that is almost perfect.
  • dmunsie - Wednesday, October 30, 2013 - link

    "Location Spoofing. Let us set location services to lie to apps temporarily. This is useful for a variety of reasons ranging from development to privacy."

    Developers can already do this, so what you are really asking is for privacy reasons. And in that case, Apple allows users to turn off location services on a per app basis already. I can tell you already that Apple is not going to allow users to spoof location data to any apps -- either you give an app accurate location data or no location data. Anything else puts their relationships with developers at risk -- for example, MLB would almost certainly pull their app if users could say they were in a different location since they wouldn't be able to enforce the blackout rules (I personally hate the blackout rules, but since they are legal agreements, MLB has to abide by them).
  • tigmd99 - Wednesday, October 30, 2013 - link

    NFC? Dude, get updated! NFC (and Google Wallet) is a dying technology!!

    iBeacon and AirDrop are killing NFC.
  • algalli - Wednesday, October 30, 2013 - link

    NFC is a dead issue. Most people have IBeacon which should be far more useful to stores and customers than NFC was ever intended to be. It is innovative if not yet widely recognized.

Log in

Don't have an account? Sign up now