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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synaesthetic - Sunday, March 20, 2011 - link
Touchscreens are the very antithesis of good ergonomics. Unless haptic feedback can defy physics or we get some deformable/flexible screens, devices with actual buttons will always be superior.The human brain simply reacts better to physically pushing a button. Touchscreens have horrible ergonomics--a tiny bit of vibration is not really much haptic feedback. It feels like a lot to us (and it certainly helps me on my phone) but it only feels like that beccause a touchscreen is so far away from any semblance of "natural use."
Touchscreens should be used when they are REQUIRED--such as on smartphones, where the number of controls, commands and options far outstrip the physical size of the device and the physical space to place buttons.
I don't think tablets will ever stop being a toy.
stephenbrooks - Saturday, March 19, 2011 - link
Page 2, final picture. The iPad 2 is on the BOTTOM not the top there.Anand Lal Shimpi - Saturday, March 19, 2011 - link
Fixed! Thanks :)Omid.M - Saturday, March 19, 2011 - link
"There's also the idea of synergy among devices. Even if you play within the Apple universe and own a Mac, an iPhone and an iPad, there's no magical way of sharing data and applications between them. I should be able to work on my Mac, step away and have my apps/data come with me. Your best bet is something like Dropbox but that's no where near the type of cohesive solution I'm talking about. Think HP's webOS touch-to-share but on steroids and you're on the right track."Anand/Brian/Vivek:
I'm sure that's what Apple is planning with NFC-enabled iOS devices, but then wouldn't that require a saved state to be stored in the cloud and then re-downloaded on demand on the next device used? I would imagine that "lag" in the UX would be a problem. How long would you feasibly have to wait for stuff to download the first time you sit down with a new device (new as in rotation) ?
Also, would this be limited to stock-Apple stuff only? It would be a bear for Apple to save the state of arbitrary 3rd party software from one device to the next (assuming both devices have the client installed). Right?
Next...
"So if you're actually torn between the iPad 2 and the Xoom my best advice is to wait. Apple needs to update iOS in a major way and Honeycomb needs a hardware update. Whichever gets it right first should get your money."
This is really the money statement of the review. I think Android tab makers need to NOT simply look at the iPad 2 to figure out their next move, but to pave their own path, not for the path to be a RESPONSE to the competition. The Xoom should have higher quality display for sure, and Honeycomb needs faster incremental updates. I really liked it but it just lacks so much in terms of functionality and compatibility, at least if we're considering it for productivity.
None of the tabs on the market right now are really meant for editing/creating content--even if you're able to with a handful of apps--but simply consuming existing content (iTunes music streaming, sharing videos, social networking--and I think that's the biggest issue with tablet to replace netbooks or become devices taken seriously.
Please, please cover the WebOS tablet when it comes out.
Thanks for the review, guys. Great work. The technical section on glass, for instance, is one reason with AT does the best reviews.
Worth the read. Will tweet for others to check it out!
-Omid
clb - Monday, April 4, 2011 - link
I agree on both, but the point on #1 is missed. It is not the need for the cloud on NFC, but the fact that you cannot actually sync the device:>I should be able to work on my Mac, step away and have my apps/data come with me.
Even if you are going from a Mac to the iPad (1 or 2), there is no sync feature that covers everything. A note created on the iPad has to be emailed to your Mac; Apple will not let you read a note created on the iPad on a Mac unless you email it to yourself! And there is no way to get a note into the Likewise, using DropBox is great, but now files have to be loaded up, then you must reconnect, then load down. You cannot simply have the Mac send to the iPad or vice versa.
This is because unlike the early iPods, the iPhones and iPads do not allow the user to move files. Early iPods could be treated as FireWire drives. Not the iOs devices. Everything must go through iTunes or via the cloud (i.e., third-party sites). If I'm at a beach house with no cloud connection, and want to move content from my PC/Mac to my iPad, I'm SOL in many cases.
This is bad.
Adam Chew - Saturday, March 19, 2011 - link
Judging from your review of the iPad, its competitors will stand no chance of ever gaining traction in everyday use.So get a Macbook Air.....LOL
The problem is the everyday user is not a tech blog blogger, the iPad is ideal for consumption of everything of the net and not like some tech blogger who needs to blog unnecessarily with a laptop when an iPad is at hand.
nickdoc - Sunday, March 20, 2011 - link
Loved your contribution! The geek talk was getting really boring and repetitive. Hello! Normal people have needs, too. This is what the reviewers often forget. Not everyone needs to create content to be consumed by other creators of mostly the same content. Lol!stephenbrooks - Saturday, March 19, 2011 - link
OK, why where you joining *two iPads* together with magnets and buying a "smart vase" from Apple? :D"The iPad aligns and attaches to the body of the iPad 2 using six magnets along its side that line up with a similar set of magnets on the device. When I acquired the smart vase at launch, I [...]"
Anand Lal Shimpi - Saturday, March 19, 2011 - link
Fixed again :)tipoo - Saturday, March 19, 2011 - link
How the f does it work?