This is where iPhones are expected to shine, and the iPhone 5S really rather does, even two-and-a-bit years down the line. Apple decided to push harder with the camera sensor in this handset, trying to create something squarely between the HTC One M8 and Samsung Galaxy S5 – two of its main competitors in 2013 – and beat both.
It mostly pulled it off too, although the other two flagships of that year were also really decent snappers, and in many ways were also class-leading – for instance, there's no background de-focus here with the iPhone 5S.
Let's dial it back a little and explain: Samsung is all about staying true to the 'megapixel wars' and wants to cram as many as it can in there, which is why it has such a complex sensor. It can't function as well in low light, but get the shot composition right and you're going to get some really nice snaps.
The approach HTC took with the One M8 was almost the opposite: it enabled you to get some really great low light shots thanks to the improved Ultrapixel camera. It only sports a 4MP sensor, but with much larger pixels which let in more light.
This means better night time performance and a faster shutter, and with this camera you get a wider gamut of shots to take away with you, although you probably won't want to blow them up for the wall. (HTC has since rejoined the megapixel wars with the HTC One M9.)
The iPhone 5S, as I said, falls in between these camps, coming with an 8MP sensor and pixels 75% the size of the HTC One M8's offering. The result is a strong blend between sharpness and low light ability, where the iPhone straddles the categories without being market leading in either back when it first appeared.
That said, the updated camera interface, combined with the A7's ability to easily combine three snaps to make the best picture it can, mean this is a truly awesome camera phone.
The UI of recent updates enables you to simply slide between modes, be it panorama, a new 'square' mode for social networks, the standard photo, video at 1080p or the all new Slow-mo mode, which can capture 120 frames per second at 720p resolution and gives you the option to choose when the slow down and speed up happens.
There's also a new timelapse mode now, which lets you use the iPhone 5S to capture videos over a very long period of time. A timer and exposure control have also been added to the Camera app since the handset first went on sale.
The CPU is at its best here, with the shutter speed really great, the burst mode working well (simply activated by pressing the shutter button for any length of time) and giving seemingly unlimited shots. The iPhone can also intelligently work out the best shot and the suggestions usually get it pretty bang on, where other handsets with the same functionality can't every time.
Apple was pretty late to the burst mode game, but it's implemented it in a way that really works rather well. At least the ability to lock focus is on board, as well as locking exposure - these are closer to pro-photographer moves, and allow for some interesting shot composition.
The UI is a something of a bugbear though, despite looking so flashy. The options to enable HDR mode, turn the flash on and off or change to the front facing camera don't always want to come on when you tap, which makes it hard to use the camera when you're trying to take an arty shot in lower light that doesn't need the flash.
Auto HDR mode, ushered in with iOS 7.1, is another cool feature. This will fire up automatically when light levels are going a bit all over the place and will give you a much richer (if slower to snap) picture without you needing to mess about with the settings.
Clever work from Apple – it's up there with the real-time HDR introduced with the Samsung Galaxy S5.
This leads me nicely onto the other big change over the iPhone 5, with the flash getting something of an update thanks to an increase to dual LED. This is nothing new in smartphones, but Apple's been smart here as well, thanks to bringing a white and amber option into play.
What this allows the iPhone 5S to do is analyse the scene with a primary flash and then mix the amber and white colours together to reproduce colours more accurately and stop everything looking so washed out.
It's actually a more impressive feature than I thought it might be when it comes to colour rendition, but I can't say it made me want to use the flash any more than normal. As per usual, it got turned off pretty soon and didn't come back on again, which is partly due to the impressive low light performance.
To summarise: the iPhone 5S camera beats its predecessors by some distance, thanks to its simplicity of use and the great modes on offer (there's even an area that allows you to choose a filter before you start snapping, with real time previews so you can check each one out.)
That's actually something that I found a little odd: when you pull a filtered photo from your iPhone 5S onto your computer, the filter has been removed. However, share it through Airdrop or in the Mail app and it will display with Chrome or Mono or whatever filter you went for.
However, that's a terribly minor niggle compared to the hugely impressive camera, which I urge you to try with a little more depth should you get the chance. I would like to see Apple enable 16:9 photos at some point soon, as the UI doesn't lend itself to the 4:3 options that come out.
I understand Apple is trying to stay close to more professional photography, but most phones make full use of the screen, and it would be great if Apple followed suit.
And what of the iPhone 6, iPhone 6 Plus, iPhone 6S and iPhone 6S Plus cameras? Is the extra expense justified in the extra photo quality? Well, the 2014 phones feature some subtle upgrades that leave your pictures looking better than ever, while the 2015 pair ups the number of megapixels.
The iPhone 5S can still hold its own in the photography department, but real enthusiasts should consider one of the latest models; particularly the two Plus models, which offer optical stabilisation.
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