Battery Life

The iPhone XS comes with a 2658mAh/10.13Wh battery, while the XS Max has a capacity of 3174mAh/12.08Wh. Again, it’s to be noted that although both phones are quite large form-factor devices by now, Apple’s battery density still largely lags behind the competition. While yes, it’s true that the XS Max’ battery is the biggest that Apple has ever used, it still pales in comparison to the 3500 to 4000mAh that other vendors now employ in the same form-factor.

As we saw in the SPEC analysis, the one advantage that Apple has is an enormous lead in terms of power efficiency of its SoC, which largely makes up for any gap in the battery capacity deficit.

Our web browsing test is a mixed-to-heavy workload that iterates through a set of popular webpages that are hosted on our server. The test loads a web page, pauses, scrolls through it, pauses, and then continues to the next in the set, repeating all over when done. Brightness is fixed at 200cd/m².

Web Browsing Battery Life 2016 (WiFi)

The iPhone XS saw a very slight degradation compared to the iPhone X in our test. The 19 minute deficit isn’t terrible, but it does come at a surprise given that Apple had promised improved battery life for the new model. What’s happening is that likely our test is a tad heavier in its workload than what Apple and many other vendors internally test to advertise as the daily battery life of their devices.

The iPhone XS Max came in at 10.3h. Again while this is still good, it’s a degradation over the 11.83h of the iPhone 8 Plus. Here it’s easier to rationalise the difference; the OLED screen of the XS Max is just more power hungry and also has a larger area than the iPhone 8 Plus. Here the increased battery capacity isn’t enough to counteract the panel’s increased needs.

As to why the iPhone XS saw a degradation over the X, I’m not too sure. I did rerun the test on the iPhone X to make sure iOS12 hadn’t impacted the devices – and I got a runtime just 10 minutes lower than what I had tested on the iPhone X back around in January, so the iOS upgrade certainly doesn’t seem to have affected the battery life.

It should be relatively safe to assume that the new A12 should be more efficient in its workloads, even with the increased performance that it brings. One thing that we can’t really verify is the power efficiency at intermediate performance states, as that’s also where CPUs perform a lot of their work at.

We also have to keep in mind the connectivity factor: the new iPhone’s seems to sport a new Broadcom BCM4377 WiFi combo chip which we don’t know much about. Most importantly the new XS have also switched over from a Qualcomm baseband (in our test unit of the iPhone X) to a new Intel XMM7560 baseband.

I’ve generally given up on LTE testing after a few years ago I had run into some serious issues regarding a misconfiguration of my mobile carriers’ baseband stations as they did not have CDRX enabled. This caused an almost 20-30% battery life degradation on Huawei’s devices – and if I hadn’t debugged the issue with HiSilicon I’d probably be none the wiser. Fact is, cellular battery life testing is a lot harder than one would think, and without having a controlled environment, I’m very hesitant to resume cellular battery life testing.

That being said, I will revisit the iPhone X vs iPhone XS battery life topic while on LTE over the weekend and post an update to the review.

Overall, the battery life of the iPhone XS and XS Max are good – they don’t quite reach Apple’s claimed improvements, but that also just might be something that will vary from use-case to use-case.

Display Measurement & Power Camera - Daylight Evaluation: Zoom and Scenic
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  • NICOXIS - Friday, October 5, 2018 - link

    I wonder how A12 would do on Android or Windows... I'm not into Apple but they have done a fantastic job with their SoC
  • LiverpoolFC5903 - Tuesday, October 9, 2018 - link

    Probably nowhere as good as it is projected here.
    What is the bloody point of these supposedly super fast SOCs with massive caches and execution units when the OS running on it will be the highly limited, crippled and locked OS like the IOS. No emulators, no support for USB peripherals like gamepads, mice or keyboards, poor excuse for file management, no access to outside apps, no ability to run non webkit based browsers, no ability to seamlessly transfer data to and from windows desktops and multiple other limitations.

    All and well getting excited over this SOC but its like Having a 450 BHP ferrari running on a 80 mile speed limiter with an automatic transmission. All that power is useless and will remain unutilised.

    Until they allow other OS to run on their hardware, the comparisons are meaningless. I can do a hell lot more on a pithy 835 than I will ever be able to do on an A11 or A12.
  • iSeptimus - Tuesday, October 9, 2018 - link

    Wow, so much wrong with this statement.
  • bulber - Friday, October 12, 2018 - link

    You are wrong and I know you are too narcissistic to realize that. I would pity you but your username tells me you don't deserve any pity.
  • Barilla - Friday, October 5, 2018 - link

    Fantastic hardware (well, except the notch), shame it's only locked to one OS. Would love to see an Android phone with hardware like that.
  • Matte_Black13 - Friday, October 5, 2018 - link

    Well Qualcomm is working on quite a few things, new SoC, NPU, and Samsung is totally redesigning their GPU, so...maybe sooner than later (S10)
  • varase - Friday, October 5, 2018 - link

    It'll be interesting to see what comes of that effort - so much of the Android market is feature phone replacements - the actual percentage which represents high end flagship phones is pretty slim.

    If a bigger percentage of the Android market is willing to pay for silicon with that increased compute capacity, there may be hope.
  • melgross - Saturday, October 6, 2018 - link

    But will they? Microprosser Reports says that each new SoC from Apple cost, the year of introduction, between $34-38. Top Android SoCs cost between $24-28. That’s a big difference. These phones compete wither each other, and price while Apple mostly competes against itself.
  • melgross - Saturday, October 6, 2018 - link

    The reason, or I should say, one of the reasons why other manufacturers are copying Apple’s notch, is because it allows a full screen phone. Notice that Samsung has edge to edge, but still retains a shorter screen on both the top and bottom. The notch removes 2-3% of the screen area, depending on screen size, which is very little. Now take the Galaxy 9+, and you’ll notice that when the entire top and bottom cutoffs are added together, it amounts to about 10% of the possible screen size.

    It’s why the new Pixel and others are moving to the notch. In the cases where the notch is just being copied, it’s ridiculous, because those companies are still using a chin on the bottom, and the notch is just there to copy the iPhone.
  • id4andrei - Saturday, October 6, 2018 - link

    No. They are copying the iphone for the look. If they were copying to maximize screen area they would copy Essential. Apple removed the chin and the notch is needed for face id - they have a good reason. Some copycats(not all) ape the look and keep the chin. A good compromise is the impending OnePlus T. It has teardrop notch and minimized chin that makes it look actually good. Asus is on the other side of the spectrum. They even bragged they wanted to copy the look of the iphone X.

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