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iPhone 6 vs iPhone 5s – should you get Apple’s new mobile?

iPhone 6 vs iPhone 5S

Can't decide to keep your iPhone 5S or upgrade to the iPhone 6, or are just wondering which to buy? we'll give you the answers you need

With its latest phones, the iPhone 6 and the iPhone 6 Plus, Apple has joined the big-screen revolution, with its biggest smartphones ever. On top of that, each handset has the usual range of upgrade features over the iPhone 5S, which remains on sale. One of the questions existing iPhone 5S owners are likely to have is, is it worth upgrading? That’s what we’re here to help with, as we examine both handsets and give you all the information you need to make a decision. We’ve had chance to review all of the phones in detail, so we’re fully prepped to find out which phone’s best for you.

Given the size of the iPhone 5S, we’ve decided to compare it to the iPhone 6 only; the iPhone 6 Plus is a much bigger handset that competes with other large-screen phones. For most people, the iPhone 6 is a more logical upgrade from a 5S, particularly if you still want a handset that you can easily carry around.


Dimensions: The iPhone 6 is a big handset compared to previous iPhones but it still only measures 138.1 x 67 x 6.9mm and weighs 129g. The tiny iPhone 5s, by comparison, measures 123.8 x 58.6 x 7.6mm and weighs 112g. This makes the iPhone 6 0.5mm thinner and only a fraction heavier than its predecessor – an impressive feat considering that it has a much larger 4.7in screen, compared to the 5S’ 4in screen.

Whether or not you find the iPhone 6 too big really comes down to personal preference. We think it’s one of those things that’s easy to get used to. When we first picked up the iPhone 6 it looked and felt massive compared to the iPhone 5S; after using the new handset for a short period of time, the iPhone 5S looked tiny.

In terms of usability and how it feels, the iPhone 6 remains a one-handed phone, and it’s easy to store in a pocket or bag. If you were worried that the newer handset would simply be too big to carry around, don’t; it’s a great size and we think it strikes the perfect balance (for most people) between physical size, screen size and usability. In other words, don’t hold off buying the new phone because you don’t want something too big.

Materials: The iPhone 5S was already a thing of beauty but the iPhone 6 is even more desirable and looks more modern. It has an anodised aluminium rear panel, a curved glass front that smoothly swoops down to the metal sides and a stainless steel Apple logo on the back of the phone. This curved edge makes it much more comfortable to hold than the iPhone 5S and that bit more grippy, which is important given its larger size.

The iPhone 5s, meanwhile, is also made of anodised aluminium but has diamond-cut chamfered edges. Its full metal body is incredibly tough and feels fantastic to hold and still looks great even after a year of full-time use. It’s squarer edges give it a different appearance, but suit a phone of this size. 

Design conclusion: Both of Apple’s handsets are high-quality premium products, both incredibly well designed for their respective sizes. Upgrading to the iPhone 6 certainly doesn’t get you a better-made product, although it’s down to personal preference as to whether it looks better or not. While the iPhone 5S is easy to carry around, as it’s so small, we don’t think that the iPhone 6 loses out by being bigger: in fact, we think that it strikes the perfect balance between size and usability.


Screen size: The iPhone 6 has a large 4.7in screen. We feel this is one of the best and most practical screen sizes currently available, as it’s easy to reach all parts of the screen no matter how big or small your hands are. It’s also not a big jump from the iPhone 5S with its 4in screen, which was definitely a one-handed phone to use.

That said, just in case the jump from the tiny Phone 5s is too great, Apple has included its brand new Reachability feature in the iPhone 6. This new control, which you activate by double-tapping the TouchID button, makes the entire screen slide down to the lower half of the display, so you’ll always have the top of the screen within reach at all times. You don’t need to use this feature very often, as most of the screen is within easy reach of a thumb, but for those occasional times that you need it Reachability does a useful job.

Screen resolution: The iPhone 6 has a 1,334×750 resolution while the iPhone 5s has a smaller 1,136×640 resolution. This seems like a decent jump in numbers, but the sharpness and clarity of the display stays roughly the same, as both phones have a pixel density of 326PPI (pixels-per-inch). In terms of pure sharpness, then, both screens look the same. However, Apple has used the extra resolution on the iPhone 6, with a new wider keyboard that gives you extra buttons, such as cursor keys, and a home screen that fits one more row of icons on it.

You shouldn’t underestimate the benefits of having a larger screen, as the extra space makes a big difference day-to-day: web pages are easier to navigate and see, photos look better and apps are that bit more comfortable. As we said earlier, the iPhone 6 manages to strike the perfect balance between screen size and physical phone size; the iPhone 5S’s screen now feels cramped in comparison.

Screen technology: Apple has traditionally always used IPS LCD screens for its iPhones, and the iPhone 6 is no different instead. IPS offers several advantages over LCD, as this type of panel technology can produce more accurate colours and better viewing angles. The new panel inside the iPhone 6 is even better.

While the iPhone 5S’s screen is bright at 502cd/m2 it’s contrast ratio of 972:1 isn’t great by today’s standards. With the iPhone 6, we measured brightness at 543cd/m2 and a contrast ratio of 1,456:1. That means that it’s more than bright enough to view in daylight, while you get all of detail in both the light and dark parts of an image. Side-by-side there’s no real contest, with the iPhone 6’s display better in virtually every way.

Apple has said that the iPhone 6 has a “dual-domain” pixel structure, which is meant to improve viewing angles even further. This essentially means the subpixels in the display have a slightly skewed arrangement so they can deal with uneven lighting more efficiently. It certainly works, while the iPhone 5S’ viewing angles are great, at some angles the screen takes on a slightly purplish tint; you can look at the iPhone 6’s screen at any angle and it looks the same.

Display conclusion: There’s not much to tell to the two screens apart, aside from size and resolution. Retrospectively, after using the iPhone 6, the iPhone 5S looks small, but the older handset certainly isn’t too small and it’s still perfectly good for every app, web browsing and emailing. That said, we actually prefer the bigger screen of the iPhone 6. More screen resolution and a larger display makes apps, web browsing and photos look that much better. A slightly larger screen isn’t a great reason to upgrade, though, and if you’re happy with your iPhone 5S, you may want to wait a generation to upgrade to the iPhone 6S.


Processor: The iPhone 6 has one of Apple’s brand new 64-bit A8 chips. Apple says this will have a 25% faster CPU and 50% faster graphics than the current A7 chip in the iPhone 5s, so performance should be significantly improved. This is definitely true. For instance, the iPhone 5s scored a super fast 416ms in our SunSpider JavaScript benchmarks, but the iPhone 6 completed the test in 384ms. Graphics performance was also far superior on the iPhone 6, scoring 17,509 in 3DMark’s Ice Storm Unlimited test, compared to the 14,506 of the iPhone 5S.

While the iPhone 6 is quick, the performance increase isn’t as much as between the iPhone 5 and the iPhone 5S. The real question is, is the iPhone 5S too slow? The answer is, of course, no. With Apple’s older handset you can run iOS 8 at full speed, every game without slow down and rendering web pages is no problem. Again, there’s no compelling reason to upgrade based on this spec.

Battery: Apple has never revealed the mAh ratings for its phone batteries, but teardowns have shown us the true specifications, with the iPhone 5S having a 1,560mAh battery. It lasted 14h 31m in our own continuous video playback testing. The iPhone 6 has a larger 1,810mAh battery. It has a more efficient SoC, but it also has a much larger screen to deal with. In our video playback test, the phone lasted for 12h 58m, which is a little less, but not dramatically so. However, using the phone all day, where it was synchronising email accounts constantly in the background without the screen being on, the iPhone 6 did much better than our iPhone 5S, easily lasting a full day on a charge. We found that we had to charge our iPhone 5S much more frequently, so in real-use the iPhone 6 is a big improvement.

Storage: The iPhone 6 is available in 16GB, 64GB and 128GB models. Strangely there’s no 32GB version, and the phone doesn’t support microSD cards either. In fairness to Apple, the price of the 64GB iPhone 6 is the same as the original price of the 32GB iPhone 5S; this is the best model for most people to buy. The iPhone 5s, on the other hand, is only available in 16GB and 32GB versions, with the 64GB version now withdrawn from sale. It also doesn’t support microSD cards.

Performance conclusion: Raw CPU and graphical performance is better on the iPhone 6, but not so much so that an upgrade is worthwhile. The real benefit is in day-to-day battery life, where our iPhone 6 model lasted much longer than our iPhone 5S, which needed to be topped up more regularly. Even so, that’s not a big reason to make the jump now if you’re happy with the iPhone 5S.


The iPhone 6 keeps the same 8-megapixel camera and True Tone flash as the iPhone 5s, but the big new addition to the iPhone 6’s sensor is its phase-detect autofocus. It uses the same dedicated focus site technology as DSLR camera, allowing you to focus much quicker than your average smartphone camera.

iPhone 6 vs iPhone 5s cameras

The iPhone 6 camera also has digital image stabilisation to help reduce hand shake. It’s a shame it doesn’t have optical image stabilisation like the iPhone 6 Plus, but its video capabilities have also been improved. You can now shoot video in Full HD at a multitude of different frame rates, including 30fps and 60fps as well as slow-mo video in 120fps and 240fps. The iPhone 5s’s camera, by comparison, is only able to shoot Full HD video at 30fps and slow-mo video at 720p at 120fps. Apple has also improved the sensor and image processing, so the iPhone 6 captured more detailed images in bright light, and exceptional low-light images; in contrast, the iPhone 5S produced quite noisy low-light images. You can compare the iPhone 6 (top) to the iPhone 5S (bottom) in low light and brightly-lit scenarios below – click an image to view the full resolution photo.

iPhone 6 sample shot Star Wars bright light

Apple iPhone 5S camera test

Camera conclusion: You don’t gain anything in terms of resolution by upgrading to the iPhone 6, but you do get a new slow motion mode, better dynamic range and less-noisy low-light images. As to whether this makes a difference, it really depends on how much you use your phone’s camera.


The iPhone 5s was the first phone to have a built-in fingerprint sensor in the form of its TouchID sensor, so it’s only natural that the iPhone 6 has one as well. This allows you to unlock the phone in less than a second using your finger, as well as confirm payments on the App Store. Apple has, as of iOS 8, opened up the system, so that third-party app developers can also use the fingerprint sensor. Few do so at the moment, although support is growing. Of course, app support is there for the iPhone 5S and iPhone 6.

Apple as improved the TouchID sensor in the iPhone 6 slightly: with the iPhone 5S we found that it wouldn’t recognise a fingerprint after we had washed and dried our hands; the iPhone 6 does.

TouchID can also be used to authorise payments via Apple Pay, which has yet to launch in the UK. With the iPhone 5S you’ll be able to do this for online transactions, but you’ll need an Apple Watch and its NFC sensor for it to work with contactless; the iPhone 6 has an NFC chip inside it already. Apple Pay is a slim reason to upgrade now, unless you live in the States, really don’t want to use credit cards and shop exclusively in stores that support it.

Both phones also have an accelerometer to keep track of the number of steps you take each day, but the iPhone 6 adds a barometer to the mix so it can take account of elevation, giving you more accurate results in Apple’s new Health app for iOS 8. The iPhone 6 can also tell the difference between cycling and running. Even so, if you really want to track your health, a dedicated fitness tracker will do a better job than either phone.

As you’d expect from an Apple device, Siri comes as standard, so you can use both phones hands-free. Siri’s voice control also lets you use your voice to send messages, set reminders and identify songs. 

Each phone is also compatible with Apple’s brand new Apple Watch. This smartwatch will only work with iOS devices, ruling out any crossover with Android phones. The Apple Watch will be available in two sizes, three finishes and six different straps, making it one of the most customisable smartwatches we’ve seen so far.

A smartwatch is also a practical accessory for anyone with a large screen phone, as it means you won’t have to continually fish it out of your bag each time you want to respond to a message or email. Instead, you can use Siri to reply to messages using your voice and read your notifications straight on your wrist. It can also be used a remote viewfinder for a paired iPhone camera. The Apple Watch won’t be released until next year, but in the mean time you can read all about Apple’s smartwatch in our in-depth Apple Watch article.

Features conclusion: There’s surprisingly little between the two handsets, bar the NFC chip in the iPhone 6. Given that this chip is just for Apple Pay and that the payment system isn’t widely supported, it’s not a big reason to make the upgrade.


Both phones now support iOS 8: the iPhone 6 ships with it, and the iPhone 5S can be upgraded to it. In terms of OS features, both phones have exactly the same range, except where hardware limits it. As noted earlier in this article, that means that the iPhone 6 gets a 240fps Slo-mo mode, due to its better processor, and a bigger and better keyboard, due to its larger display. There’s really very little in it, though, and both phones run the OS extremely well.

Both phones can use the excellent new features that let you share features across your phones and Mac OS X Yosemite computers. These include using Continuity to answer iPhone calls and send/receive text messages from any device, and using Handoff to start a task one device and finish on another.


Although it’s a year old, the iPhone 5S is still an extremely good smartphone, competing, performance-wise, with the current crop of flagship Android phones, and not far behind the iPhone 6. It would be hard to argue that the iPhone 6 isn’t a better smartphone overall, as it’s faster, has a better camera, a larger screen with more resolution, and day-to-day battery life is better.

If we were buying a new phone now, we’d buy the iPhone 6 over the iPhone 5S any day. Choosing whether to upgrade or not is a harder decision, given that there’s not a lot separating the two handsets. Although we prefer the larger screen of the iPhone 6 and wouldn’t want to go back to the smaller iPhone 5S that’s mostly because we’ve had chance to get used to the bigger screen; before we made the upgrade we were perfectly satisfied with the 5S’s 4in display.

Our general feeling is that unless the bigger screen is a must-have, there’s no compelling reason to ditch the iPhone 5S today; instead, waiting until September until the iPhone 6S comes out makes a lot of sense.


ModeliPhone 6iPhone 5S
ProcessorDual-core 1.4GHz Apple A8Dual-core 1.3GHz Apple A7
Screen size4.7in4in
Screen resolution1,334×7501,136×640
Screen typeIPSIPS
Front camera1.2 megapixels1.2 megapixels
Rear camera8 megapixels8 megapixels
FlashYes (dual LED)Yes (dual LED)
Memory card slot (supplied)N/AN/A
BluetoothBluetooth 4.0Bluetooth 4.0
Wireless data4G4G
Operating systemiOS 8iOS 7.1
Battery size1,810mAh1,560mAh

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