Apple's iPhone 4: Thoroughly Reviewed
by Brian Klug & Anand Lal Shimpi on June 30, 2010 4:06 AM EST- Posted in
- Smartphones
- Apple
- iPhone 4
- Gadgets
- Mobile
Incredible Battery Life
I’ve publicly praised Apple for its honesty in reporting battery life over the past couple of years, and the iPhone 4 gives me no reason to stop.
The 4 has an integrated 5.25Whr battery. That’s around 95% of the battery capacity of the HTC EVO 4G, despite having much lower power frequirements. It’s also a 16% increase over the 4.51Whr battery that was in the iPhone 3GS. This means at bare minimum, assuming the iPhone 4 doesn’t draw any more power than the 3GS, we should get 16% more battery life.
In reality, we get much more.
When Apple introduced the iPhone 3G it dropped battery life to a level that we’d been stuck at ever since. The 3GS improved battery life a bit through better CPU power efficiency but you still didn’t have enough juice to get through a day without charging.
The iPhone 4 changes all of that. The combination of a larger battery and a more power efficient SoC results in an incredible amount of battery life.
Our first test is a basic web browsing benchmark. We've scripted almost two dozen webpages to load, pause for 20 seconds, then forward on to the next page. None of the pages use any Flash. This process repeats until the battery is dead. Screen brightness on the iPhones was set to 50% and the screens remained on the whole time.
Battery life improved nearly 38% with the iPhone 4. It's clear that while the A4 improved performance, the real improvement was in battery life. This test has enough idle time where good power management and low idle power can really impact the results. There's simply no other similar smartphone that can touch the 4's battery life.
We then repeated the same test over WiFi instead of 3G:
Apple claims the iPhone 4 will last for up to 10 hours over WiFi, we measured just under that at 9.96 hours. The improvement here is only 12.8%, which tells me that we're nearing the limit of how efficiently Apple can manage power in WiFi mode. There's a wall that we're quickly approaching with this current architecture.
To measure talk time we play MP3s on repeat into the mic of a phone and use it to call the phone being tested. The process continues until the test phone dies. In this case the screen is allowed to go to sleep, as it normally would be if you were talking on the phone:
Apple promised up to 7 hours of 3G talk time with the iPhone 4. We measured 7.47 hours. That's an increase of 54.9% over the iPhone 3GS. While in a phone call the majority of the A4 SoC is powered down, so the efficiency improvements here have to do with how much less power the A4 consumes while off and the new Skyworks 3G modem (the iPhone 3GS used an Infineon modem).
In our iOS 4 review we looked at the impact multitasking had on the iPhone 3GS' web browsing battery life. I ran our 3G web browsing test while playing music through Pandora in the background. I repeated the test with the iPhone 4 for today's article:
We actually see our largest battery life improvement in this test. With a 57.7% increase in battery life over the 3GS, the iPhone 4 is not only more efficient at idle workloads but also when the SoC is constantly busy. The A4 SoC is rumored to be built on a 45nm process compared to the 65nm SoC used in the 3GS. With a moderate increase in clock speed we should be seeing a lot of the power savings that a full node shrink brings to the table.
The battery life offered by the iPhone 4 is spectacular. My iPhone 3GS could hardly get through a full day of work while traveling, I'd always need to hunt for an outlet before heading into my dinner meeting. I'm about to take my first trip with the iPhone 4 but I get the feeling that I might finally be able to make it through dinner.
Early reports of 20 and 30 hours of battery life are simply exaggerated. They're only possible if you let the phone idle in your pocket for the majority of that time. In other words, if you don't use the phone it lasts for a long time. While that's a testament to the platform's incredible idle power, the real world usage is good enough to stand on its own. It's better than any iPhone or Android phone I've tested thus far.
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The0ne - Wednesday, June 30, 2010 - link
Actually, Anand likes the performance of the iPhone and i don't blame him. It is smooth, well implemented and thus makes using it more enjoyable, quantifiable or not. Features be damn, what counts is how a user perceives the device he/she is using. And once attached or rather use to them it's hard to like something that isn't the same or better.For the most part, android OS and WebOS are fine for the vast majority of users. The slight sluggish performance is really not hindering anyone from doing anything practical. It is really just a matter of perception.
As for features and design, I can honestly say unless you been in the design phase yourself many decisions are made prior to production. Missing features such as Flash memory support is a choice left out purposely. Don't kid yourself they are doing it because they either can't or because of lack of money/resources.
mesiah - Thursday, July 1, 2010 - link
I don't agree with the flash memory support. Flash memory is so cheap to implement that it comes on the cheapest of cheap products. And before anyone uses the excuse of "a flash port would clutter up the phone and make it look ugly" Look at the huge ugly connector port used to sync / dock an iphone. Compare that to micro usb. You don't think they could shrink that thing to a quarter of its current size, or less, and add in a flash memory port? Hell, A smart engineer could make a docking port that doubles as a flash memory port (makes me wonder why we haven't seen this yet.) The reason you don't get upgradeable flash memory is the same reason you don't get removeable batteries. There isn't money in batteries and memory, the money is in forcing people with outdated hardware to upgrade.The0ne - Thursday, July 1, 2010 - link
Err, I think u might has misread what I was trying to say. As you've stated flash memory support is very easy and cheap to design in. For Apple not to have it means they have purposely decided against it. For example, creative labs has flash support on some of their PMP devices but it is extremely poor in design that it's unusable. That's the other caveat to just putting features in and not properly supporting it.Anand Lal Shimpi - Wednesday, June 30, 2010 - link
By feature parity I was referring to what's new that made it into iPhone 4: higher res screen, 45nm SoC, much improved battery life, smaller form factor. I'd expect that within the next 6 - 12 months we will see Android phones with similar specs.Software feature wise, Android is at parity in most cases and far ahead in others.
Take care,
Anand
darwinosx - Wednesday, June 30, 2010 - link
They you don't know much about either Android, the iPhone 4, or both.Mumrik - Friday, July 2, 2010 - link
Are you aware that your username undermines every single pro Apple comment you make?Also, I think most of us will take Anand's word for it over an anonymous commenter's.
mmike70 - Sunday, July 4, 2010 - link
Why does it undermine?John Sawyer - Thursday, July 1, 2010 - link
The somewhat larger number of pixels in the Retina display that Apple is using in the iPhone 4, plus its smaller size than the Evo and Droid X displays, do combine to make for a massive difference, as the pictures in the article show. I've compared the two, and the iPhone 4 display really is startlingly good. Many things don't look hugely different between the two, such as some videos, larger graphics and text, etc., but small text (which I look at a lot because that's what a lot of websites serve up) certainly does.semo - Wednesday, June 30, 2010 - link
I'm sorry Anand but I just couldn't bring my self to read your review after yet again detecting your bias towards this product. You come from an engineering background and it shows in your methods of analysis which appeals to me.Do you wait 6 hours in line for a new SSD? I detect hints of emotion in this article's introduction. I could be wrong but I always try to avoid technical reading when I suspect there is bias. It is plain to see on other technical sites where the companies' mission statement is part of the introduction but much more subtle here.
I look forward to your next SSD and chip architecture articles.
bplewis24 - Wednesday, June 30, 2010 - link
Anand is about the most objective Apple iPhone fanboy there is. There is no denying this, and it's both a compliment and a criticism. Until he can stop making subjective generalizations like this:"There is this more open, more configurable, more capable feel you get with Android that you don't with the iPhone. That can be both a positive and a negative. Android phones feel more like computers while iPhones have more of that appliance feel. It still boils down to personal preference, the 4 won't change that."
Really, Anand? Being more open and configurable can be a bad thing? We really need to stop perpetuating this myth that Androids can only be liked by "PC" geeks and people who like to dig deep into the OS. The reality is that Android devices don't force you to customize if you don't want to.
I'm also fairly certain that the "scrolling" issue which isn't present on my Moto Droid has something to do with the live wallpapers eating up CPU processing power. Nevertheless, I don't experience it on my phone and to blanketly imply that the OS UI is clunky (which most iPhone fanboys cling to in every comparison) is completely disingenuous.
Until Anand can rid himself of some of this bias, he will still be known as the best and most objective iPHone reviewer on the interwebs, but the title in and of itself won't be saying very much.
Brandon