Apple's iPad - The AnandTech Review
by Anand Lal Shimpi, Brian Klug & Vivek Gowri on April 7, 2010 9:39 PM EST- Posted in
- Smartphones
- Mac
- Apple
- iPad
- Mobile
Honest Apple: Battery Life
I mentioned this in my iPhone 3GS review and I believe it bares repeating: Apple's battery life estimates have been ridiculously accurate over the past couple of years. I swear Apple must have my office bugged because my battery life numbers almost always equal theirs and they have no access to my test files.
To test battery life on the iPad I ran a modified version of the process I use for smartphones. I use the WiFi connection to browse a series of 20 web pages varying in size, spending 20 seconds on each page (I timed how long it takes me to read a page on Digg and came up with 36 seconds; I standardized on 20 seconds for the test to make things a little more stressful). The test continues to loop until the battery dies. This test is designed to simulate a relatively heavy, but realistic data load on the phone. We're stressing the WiFi radio, SoC, memory and display subsystems here. This should also be the sort of battery life you get when you are using any apps that use data (but not 3D acceleration). The display brightness was set to 50% on the iPad.
That's the test I use for smartphones, but to make it a little more stressful on the iPad I continuously played music using the iPod app, one of the only apps that's allowed to run in the background. I also told the mail app to automatically check my AnandTech email account every 15 minutes. I get a good amount of mail so this constant checking would add another realistic component to the workload. I also ran this same test on ASUS Eee PC 1001P:
The iPad came in just shy of Apple's 10 hour claim. At 9 hours and 45 minutes, it's long enough to get you through the greater part of a day. But calling Apple's battery estimates conservative is misleading. A single charge won't last you all day.
The iPad does last longer than ASUS' 1001P, however ASUS tells us that the 1005PE will buy you another 2 hours of battery life for an extra $79.
What about watching movies? Our resident smartphone expert Brian Klug put together a 6 hour loop of The Bourne Ultimatum. This was from a 1080p source but re-encoded using Handbrake's Normal profile resulting in a 1.3GB 720p rip that was looped three times.
I imported the movie into iTunes, synced it to the iPad and looped the already 6 hour loop until the iPad died. Display brightness was set to 50%, auto brightness control was disabled, automatic email downloading was also disabled.
Video playback is actually a fairly light use case. In these SoCs there's usually a dedicated video decode block, most likely the PowerVR VXD (same as in the iPhone 3GS). This block decodes each frame and sends it to the display output engine. The only things working in this case are parts of the CPU, the video decode engine, memory bus and the display engine. There's no 3D rendering and the vast majority of the CPU is idle. With this in mind, it's no surprise that the iPad can last 13.6 hours when playing back a 720p H.264 movie.
| Apple iPhone 3GS | Apple iPad | ASUS Eee PC 1001P | |
| H.264 Video Playback | 9.5 hours | 13.6 hours | 5.3 hours |
The iPhone 3GS however can almost hit 10 hours performing the same test. This gives you an idea of how much power the display is consuming on the iPad. The netbook doesn't stand a chance by comparison. The iPad was made for watching lots of movies on a single battery charge.
My final battery life test was a 3D gaming benchmark. I ran Real Racing HD on the iPad (and Real Racing on the iPhone) until the devices died. The cellular network was turned off on the iPhone 3GS and brightness was set to 50%.
Anything GPU intensive is going to be the worst case scenario for these SoCs. Here we’re stressing the CPU, GPU and memory subsystem. The added load is reflected in the battery life numbers:
| Apple iPhone 3GS | Apple iPad | |
| 3D Gaming | 3.9 hours | 8.8 hours |
The iPhone 3GS approaches 4 hours, while the iPad manages almost 9 hours while gaming. I’d also consider this to be a best case scenario gaming benchmark. A more intense 3D game could easily drop these numbers even further.
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vol7ron - Wednesday, April 7, 2010 - link
There's been rumors the iPhone 4g will be talked about tomorrow by Apple. Do you have any insight into this?vol7ron
Griswold - Thursday, April 8, 2010 - link
http://en.wikipedia.org/wiki/4gvol7ron - Thursday, April 8, 2010 - link
I don't understand the point of this link?Perhaps you want to look at: http://en.wikipedia.org/wiki/IPhone
Data Network Technology and iPhone technology are not synonymous.
A5 - Thursday, April 8, 2010 - link
Unless AT&T has suddenly deployed a 4G network (or they're going to Sprint), then this new phone isn't going to be called the iPhone 4G. Also, the stuff they're announcing tomorrow are the features of iPhone OS 4.0, not new iPhone hardware.vol7ron - Thursday, April 8, 2010 - link
I'd rather not hear about the hardware at this point, but it'd be nice to say that Apple would up the clock on the 3GS (what I have). Hearing about the OS 4.0 is nice.I thought the "G" has nothing to do do with the wireless technology network. While they both stand for "generation", Apple's iPhone/OS pair will still be called the iPhone 4G, regardless if it runs on 3G Network or CDMA technology, or if the OS is upgraded afterwards; if this is confusing, think about the iPhone 2G - it runs on the 3G network and can be upgraded to OS 3.0, but it is still a iPhone 2G due to the initial hardware/OS release.
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The developer meeting was actually quite nice. There were a few surprises, but nothing huge - just a bunch of much-needed updates :) There will more-than-likely be a few more OS4.0 goodies come June with the official iPhone 4G release.
Internet User - Thursday, April 8, 2010 - link
That's incorrect. The naming conventions that Apple typically uses were thrown out the window. The first generation iPhone runs on the 2G EDGE network. The 3G (second gen) and 3GS (third gen) both run on the 3G network. We don't know what the fourth iteration will be called. It won't run on a 4G network, but it will be the 4G iPhone.vol7ron - Friday, April 9, 2010 - link
Perhaps you are right, but I thought I remember hearing Jobs talk about the naming that went into the iPhone.Technically, I think that what happened supports your argument, but we've all seen companies change their logical naming patterns. The first iPhone, as with any first generation, was called the "iPhone", with no suffixed 1G or 2G. It wasn't until the 3G came out (on OS 2.0), where there was question about its name. I think what was talked about was that the beta versions were considered 1G; the first retail release was considered 2G; and the second was 3G.
The 3GS is where it really breaks that argument, because the 3GS was released with 3.0, so technically it would be called the iPhone 4G. Instead they stuck with the "3G" and added the "S", which they said stands for "speed". However, those "2G" phones that were upgraded to OS 3.0, still work with the 3G network, but are still considered "iPhone" (w/o the suffix, but still unofficially: iPhone 2G).
In either case, I'm willing to say that I'm wrong, since a lot of it is vague memory. That, and the fact that this article is about the iPad and not the iPhone :) I was just a little curious about OS 4.0, but I was offered an exclusive direct link on the developers briefing, so I found everything out anyhow.
vol7ron
nilepez - Thursday, April 8, 2010 - link
I don't know about AT&T, but Verizon began testing LTE last year and is deploying LTE in some markets this year. Until Apple announces they're partnering with Verizon (or Sprint) or we see FCC submissions, I'll assume it's vaporware....and frankly, I'm not switching from my Sero plan for a phone.vol7ron - Wednesday, April 7, 2010 - link
Page 2: Since this isn't the 1980s, the iPad only has three four physical buttons on the device.I might be reading it wrong but the "three four" seemed out of place. Maybe that was supposed to be a "three or four", or perhaps you were going to come back to it?
vol7ron
vol7ron - Wednesday, April 7, 2010 - link
Page 5: "Tap it twice while you're playing music and playback controls appear, Also when..."Perhaps there should be a period where the comma is and a comma after "Also"?
BTW, not purposefully checking for errors, just looking out for ya.
vol7ron