The Apple iPad 2 Review
by Brian Klug, Anand Lal Shimpi & Vivek Gowri on March 19, 2011 8:01 PM ESTBattery Life
Testing battery life on a tablet is pretty grueling as these things are effectively smartphones with gigantic batteries. What would last for only a few hours on a smartphone can easily last over ten on a tablet. The iPad 2 is no exception.
As iFixit discovered, the iPad 2 features a nearly identical battery to the original iPad (25Wh vs. 24.8Wh). We already established that display brightness hasn't gone up so the only real impact on battery life will be because of the A5 SoC.
The iPad 2 WiFi's battery, courtesy iFixit
The ARM Cortex A9 tends to be more power efficient than its predecessor, the A8. With a shallower pipeline and the ability to execute instructions out of program order you get better performance per watt in most cases. As a result the A5 should complete bursts of instructions quicker than the A4 and get back to sleep sooner.
To put this to the test we put together a battery life test that combined our non-Flash smartphone web browsing test, checking for email every 15 minutes (via a Gmail account receiving ~100 emails per day) and constant local music playback while all of this is going on. The results are pretty much as expected:
Over WiFi the Motorola Xoom and iPad 1 deliver very similar results. The iPad 2 pulls ahead by around 8%, it's not a huge advantage but it's there. Over 3G there's a noticeable drop in battery life, putting both of the iPad 2s below 10 hours and kicking the Xoom down to under 9 hours. All of the numbers on this chart are respectable however and you can expect a good day's worth of use out of any of these tablets.
Note that while the iPad 2 did better than its predecessor if you were to run an app that pegged both CPU cores at 100% you'd see reduced battery life on the iPad 2 vs. the iPad 1. Granted you'd also see better performance on the iPad 2.
Video playback is obviously an important function of these new tablets so we put together a H.264 decode playback test as well. For this test we transcoded a copy of Quantum of Solace from a 1080p BD source down to a 720p H.264 using Handbrake's Normal encode profile with one modification. In order to enable smooth playback on the Motorola Xoom we had to disable b-frames in the encode. The results are below:
The iPad 2 consistently lasted longer than the original iPad in our video playback test. The Xoom however did noticeably worse. Unfortunately only a portion of the H.264 decode pipeline is accelerated by NVIDIA's Tegra 2 in this test. When playing back anything more strenuous, portions of the pipeline are handled by the CPU cores in software. If you were to enable b-frames the Xoom would not only stutter but its battery life would drop to around 6 hours.
On the iPad 2 its Cortex A9s are mostly powered down during this test, on the Xoom the A9s are helping with the heavy lifting for video decode and as a result we see lower battery life. Kal-El is expected to address this issue head on.
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name99 - Sunday, March 20, 2011 - link
"you cant be a very tech inclined person if if you think you are, if you dont know that 1.2 GHz quad core arm cortex is coming later this year and so most tech people are waiting on that to happen"Really? You're going to buy that crappy 1.2GHz quad core A9? You're not going to wait the even better 1.8GHz quad core A15 that will be available in late 2012? Sucker!
Personally I think that if you buy now, before the 802.11s wireless spec is standardized, and before the chipsets support OpenGL 6, you're just throwing your money away. But I tell you, come 2020, that's going to be one SWEET rig that I finally get round to buying.
CZroe - Sunday, March 20, 2011 - link
"Just to test it out, I shot a series of videos of my car and stitched them together using iMovie, then added some titles and a soundtrack."I found iMovie completely useless on my iPhone 4 and iPhone 3GS because I could not combine two clips/videos nor could I make a runing commentary with titles.
Are you sure that the iPad 2 version can do this or were all the "videos" in the "series" made from the same longer video?
CZroe - Sunday, March 20, 2011 - link
"Lately Apple has been trying its hand at first party case solutions. It stated with the bumper on the iPhone 4, carried over to the original iPad, and continues now with the iPad 2."When you fix that typo ("stated" instead of "started"), you may also want to correct that fact about what came first.
The iPad launched before the iPhone 4 so the official iPad case launched before the iPhone 4 bumper case, unless I somehow missed it and the official iPad case came out mid-life for the iPad.
darwiniandude - Sunday, March 20, 2011 - link
pja: The 64gb 3G version was at most $1049 AUD rrp, before the price drop, the 64gb WiFi one was $899 AUD rrp. The 64gb WiFi was never $1100 AUD unless you were looking at eBay pricing while stock was scarce. Anyway as this article states, the iPad, provided it does what you require, is a great combination of battery life, weight and size. Tablets certainly aren't for everyone though.Deepcover96: Agreed. Hopefully this changes later and I'm sure it will, but for the moment Android has a poor selection of AAA titles. Nothing like Garageband or iMovie, but certainly nothing like Infinity Blade, Nanostudio, Beatmaker 2, World of Goo etc. I'm sure Gameloft and EA will eventually do more, provided they can monitize ok on Android. And for the limitations of iOS apps, I wouldn't be able to have an iPad as my only portable device if it were not for Pages/Keynote/Numbers/TouchDraw/Photogene and so on.
CZroe: iMovie for iPhone (last year even) could do what you ask after the first update. This year it's greatly improved. A downside to this app and other Apple apps can be a lack of well known gestures. People don't know in Pages that if you hold your finger on an object, swiping with another finger moves it by one pixel, swipe with two moves it by 5 pixels, and so on. Likewise in iMovie, you swipe down through footage like you were cutting it at the playhead to make a cut. Each cut is a faultless transition, but then you can title each cut area separately. So you cut where you want the text to change, and label accordingly. In the new iMovie (only used on iPhone 4 as I sold 1st gen iPad whilst waiting for iPad2) when you import video there are standard iOS movie trim handles over the clip, you only need import the bits you want from each clip. But you could definitely always import more videos into one project in the last version. I think Apple need a modal help "Would you like to watch a short video about iMovie?" dialog or something on the first few launches with a website link, all these apps have their features tucked away so people often think they're less powerful than they are. I'm not sure Apple is choosing the best ratio of controls to expose to the user here. And yes, iPad case came out before iPhone 4, definitely.
kschaffner - Sunday, March 20, 2011 - link
An awesome free web browser for the iPad is Terra, it gives you tabs, has an incognito mode. etc I would definitely check it out.darwiniandude - Monday, March 21, 2011 - link
Thanks, I'll check it out. I only use iCab as I bought it for iPhone, it got a universal update and I've been happy enough not to bother looking elsewhere. (it does have a 'privacy' mode) also caching of pages for when you're offline. Anyway, I've downloaded Terra and will play with it on the new iPad. It looks nice.Ha, there's a Terra Incognito HD game, lol
medi01 - Monday, March 21, 2011 - link
Looking at the rounded back of ipads, ipad2 in particular, it's hard to understand, why the newer version is easier to hold.With rounded surface, they both should be harder to hold, and ip2 in particular.
darwiniandude - Monday, March 21, 2011 - link
The original had flat sides, probably about 4 or 5mm, and a giant convex back, domed in the centre. The new one is thinner, has no flat sides (the curve just falls away from the front) but it's more of a bevelled edge, and once you're about 1cm in from the edges the back is perfectly flat.Is it easier to hold? Dunno, haven't got mine yet :) But that's what people are saying.
thebeastie - Monday, March 21, 2011 - link
Everyday I use my Ipad even when I don't think about it.I use it as my wake up Radio clock via TuneIn Radio app. This app is great as I can go to sleep with the timer and then wake up to Internet radio which beats the hell out of analog radio. I been looking at a digital radio for a while but there is no reason now for me in the world to do that, and digital radios aren't cheap, it is just another device the Ipad as replaced perfectly with much better screen interface, and life time of free updates as app software evolves.
I think the Anandtech authors here saying that they found them selfs not using their original Ipad1 after a while didn't adapt their imaginations enough of where it can be used, maybe it is something to do with age and being hardwired into their life styles, dare I say it but becoming 'old school'.
I am wondering how they wake up in the morning, I find it hard to believe there is a better way to wake up in the morning then from an Ipad radio app, if it is about sound quality there are plenty of speaker options.
For people who don't get it then I say you just don't see things the same way, I would rather shove a pine cone up my backside then wait more then 2 seconds to be able to look at my email. A laptop takes ages to boot up let a lone the loading of the email client.
The main reason I got an Ipad was because I LOVE to read the paper outside, but the wind blowing the paper around drives me nuts, the Ipad is a killer in this regard.
damianrobertjones - Monday, March 21, 2011 - link
I have an Asus EP121, 4Gb ram, SSD drive, etc. It takes 20 seconds to start from cold onto the desktop. Anotgher 2 seconds to pen my email application.Is that fast enough?
from sleep, we're talking seconds