Battery Life

Brian did some excellent sleuthing and came across battery capacities for both the iPhone 5s and 5c in Apple’s FCC disclosures. The iPhone 5 had a 3.8V 5.45Wh battery, while the 5s boosts total capacity to 5.96Wh (an increase of 9.35%). The move to a 28nm process doesn’t come with all of the benefits of a full node shrink, and it’s likely not enough to completely offset the higher potential power draw of a much beefier SoC. Apple claims the same or better battery life on the 5s compared to the iPhone 5, in practice the answer is a bit more complicated.

Unlike previous designs, we’ve never had a half node shrink for an s-SKU. Both the iPhone 3GS and iPhone 4S stayed on the same process node as their predecessor and drove up performance. In the case of the 3GS, the performance gains outweighed their power cost, while in the case of the iPhone 4S we generally saw a regression.

The iPhone 5s improves power consumption by going to 28nm, but turns that savings into increased performance. The SoC also delivers a wider dynamic range of performance than we’ve ever seen from an Apple device. There’s as much CPU power here as the first 11-inch MacBook Air, and more GPU power than an iPad 4.

To find out the balance of power savings vs. additional performance I turned to our current battery life test suite, which we first introduced with the iPhone 5 review last year.

We'll start with our WiFi battery life test. As always, we regularly load web pages at a fixed interval until the battery dies (all displays are calibrated to 200 nits).

AT Smartphone Bench 2013: Web Browsing Battery Life (WiFi)

The iPhone 5s regresses a bit compared to the 5 in this test (~12% reduction despite the larger battery). We're loading web pages very aggressively here, likely keeping the A7 cores running at their most power hungry state. Even the 5c sees a bit of a regression compared to the 5, which makes me wonder if we're seeing some of the effects of an early iOS 7 release here.

The story on LTE is a bit different. Here we see a slight improvement in battery life compared to the iPhone 5, although the larger battery of the 5s doesn't seem to give it anything other than parity with the 5c:

AT Smartphone Bench 2013: Web Browsing Battery Life (4G LTE)

Our cellular talk time test is almost entirely display and SoC independent, turning it mostly into a battery capacity test:

Cellular Talk Time

You can see the close grouping of the smaller iPhones at the bottom of the chart. There's a definite improvement in call time compared to the iPhone 5. We're finally up above iPhone 4S levels there.

AT Smartphone Bench 2013: GLBenchmark 2.5.1 Battery Life

Our Egypt HD based 3D battery life test gives us the first indication that Rogue, at least running fairly light code, can be more power efficient than the outgoing 5XT. Obviously the G6430 implemented here can run at fairly high performance levels, so I'm fully expecting peak power consumption to be worse but for more normal workloads there's no regression at all - a very good sign.

M7 Motion Coprocessor & Touch ID Camera
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  • CyberAngel - Thursday, September 19, 2013 - link

    Hurray! Reply
  • name99 - Wednesday, September 18, 2013 - link

    I imagine he would say "I heard exactly the same shit about the A6 and how it couldn't possibly be as good as I claimed. Come back when you have NUMBERS to back up your complaints." Reply
  • monaarts - Wednesday, September 18, 2013 - link

    You are mistaking a more natural transition to a 64-bit mobile world with a "PR stunt." Yes, Android will probably make a huge jump and switch to 64-bit and include 8GB of memory, or something crazy like that, but will only add to fragmentation they are already burdened with. However, Apple is trying to avoid that by building steps that lead to where they eventually want the iPhone to go. Reply
  • ddriver - Wednesday, September 18, 2013 - link

    The PC market is fragmented as well, but is still goes, doesn't it? Surely, as a bigger ecosystem, android will be slower to adopt changes. But HPC doesn't really make sense in a phone, that is why most ARM chip vendors are focusing on server v8 chips and infrastructure, which will be more lucrative than consumer electronics. v8 is the future, no doubt about it, but apple has no other winning hand besides offering v8 a little too early, knowing they can make up for the cost of the premature transition with profit margins other manufacturers cannot dream of asking for the same hardware. Surely, other brands have their fanboys too, but nowhere nearly as fanatically devoted and eager to "just take my money". Reply
  • tbrizzlevb - Wednesday, September 18, 2013 - link

    I've never had any problem with this "fragmentation" that you cut and pasted from somewhere. How exactly has that kept you from buying Android? Do you normally keep your phone for 5 years or more? I'd be willing to bet you aren't using an iPhone 3 right now.. If you upgrade your phone every few years anyways, what do you care if the first generation Droid doesn't run the latest OS update? Reply
  • AaronJ68 - Wednesday, September 18, 2013 - link

    The fact that there was never an iPhone 3 might have something to do with that. Reply
  • CyberAngel - Thursday, September 19, 2013 - link

    As a programmer I say there is a HUGE fragmentation problem with all the Androids.
    I code for Jelly Beans only and I do have an "old" 4.0 mono CPU device for testing the lag.
    Reply
  • Focher - Wednesday, September 18, 2013 - link

    You lost me when you used the phrase "apple fanboys" and "declining sales". You don't seem to understand the difference between market share versus unit sales. Reply
  • ddriver - Wednesday, September 18, 2013 - link

    So you must have taken "apple fanboys" personally, and understandably "declining sales" in a context regarding apples conflicts you. Like all other vendors, apple sales drop, thus the periodic refreshes, which do need their selling points, this time around it is v8. In the past, apple resorted to similar strategies, like making exclusive deals, purchasing the entire initial batches of new generation parts, and again making up for the cost of this "innovation" with their profit margins.

    I don't recall any other brand which pushed kids to selling their organs, do you? If that is not fanatical fanboyism, I don't know what it is...
    Reply
  • akdj - Thursday, September 19, 2013 - link

    Weird---seems to me EVERY time an iPhone is released, it sells MORE than the previous version FASTER! In fact, it's never been surpassed by another electronic item in history...and it's sales continue to climb. News Flash! Android (High end; S4/Note/HTC 1/XPeria) also sell @ a premium and almost @ the exact price of Apple's handsets. The rest of your post is nonsense. It's not just Anand's site and review praising the performance of the A7---it's ubiquitous. Is Apple paying Ars? TechCrunch? MacRumors? WSJ? Engadget? CNet?
    Dude---this is one HELL of an SoC. It's so much MORE than a 64bit chess match. A company licensing and building from the ground up a CPU/GPU/IPU that matches their OS and allows the tools to developers (For Free!) in XCode so the transition is seamless! The speed of this chip is awesome. Setting themselves up early is smart---the iPad release is imminent and has competition from both sides...Microsoft and Android. With a significantly larger 'body' and area to allow for more RAM...and future releases of other ARM based products, Apple is making in-roads within the mobile sector that ONLY bozos that cherish other brands, OEMs, or otherwise have some weird bone to pick with Apple can't realize. Mind blowing. I'm brand agnostic---use OSx, Windows and even own a couple of Android devices....but to me as dismissive as you are about the A7s build and putting it in a product the size of a pack of smokes is about as silly and should I say 'ignorant' a stance as I've seen in a long LONG time.
    This move by Apple is HUGE. Moore's law now attributed to mobile. Still a dual core. Still 1GB of RAM (albeit DDR3 vs DDR2)---yet doubling, tripling, sometimes quadrupling performance of the other 'off the shelf' SoCs on the market that other OEMs are using. It's no secret---Apple has been hiring and head hunting chip designers from Intel and AMD for some time now. These guys and gals are some of the brightest minds on earth....but you've got it all figured out and somehow Anand's been blinded by the conspiracy---as has EVERY other reviewer on the 'net.
    Un-Believable.
    J
    Reply

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