The iPhone 6S features a 4.7-inch Retina display with a 1334 x 750 pixel resolution and, well, so does the iPhone 7. While this might sound quite high, it's fairly low compared with the 2560 x 1440 pixel QHD panels found on the likes of the Samsung Galaxy S8 and HTC 10.
Although resolution hasn't improved, the screen has, sort of anyway. It doesn't go toe-to-toe with the likes of the S8, not even close, but with a wider colour gamut making the cut and a 25% increase in brightness, it's a little more easy on the eye. Apple has once again proved that there's more to good image quality that just pixel count, and when it comes to contrast levels, accurate colour representation and speedy refresh rates, the iPhone is typically without rival.
Screen's aren't just about image quality though. Toughness is a big deal too, as anyone who's spent the last nine months of their contract with a shattered smartphone screen will tell you. Here, the iPhone 7 looks set to move things one, reportedly with the adoption of the newly announced, extra tough Gorilla Glass 5 which will make case-free drops less of a death sentence.
iPhone 7 vs iPhone 6S features & performance: More power inbound
Related: iPhone 7 vs Samsung Galaxy S7
When it comes to power, Apple might not play the same specs race game as the leading Android contingent, but it doesn't need to. With every iPhone running the same software without fluffy skins, it can ensure it's more power efficient - but that doesn't mean a power boost hasn't been bestowed on the iPhone 7, though.
Apple's existing 1.84GHz dual-core A9 chip has been given a sizeable power boost, with a new A10 Fusion chipset bringing oodles of power to the mix. Do you really need that though when the 6S is already powerful enough? Difficult call. When you consider that the iPhone 7 offers 3x the power though, it's hard to look past the new handset.
More important than all that raw power, though, is that the iPhone 7 offers a major improvement that users have been calling out for for years: increased storage. Although Samsung-esque expandable storage just ain't gonna happen (dream on, dreamer), the entry-level iPhone has jumped from the 16GB adopted by the iPhone 6S, to a much more appealing 32GB.
Yes, 64GB and even 128GB models were already available, but at a massive premium, and the entry-level 16GB device was just too restrictive for many users. The new 32GB base level iPhone 7 will set a new minimum standard though and be joined by 128GB and a new 256GB model for seriously heavy users. Again, that's a good enough reason to plump for the iPhone 7.
iPhone 7 vs iPhone 6S camera: Small changes to make a big difference
The iPhone 6S's 12-megapixel primary camera is one of the best on any existing smartphone. Apple though has given it a sizeable update, patching up its weak points.
Although remaining a 12-meg offering, a new sensor 60% faster than its predecessor has been brought in. Paired with the new six-piece f/1.8 aperture lens and the iPhone 7 can take in more like to boost the phone's after-dark photo skills. Although the iPhone 6S won't disappoint on the snapping front, this could be the change that takes Apple to new levels.
The phone's True Tone flash has been upgraded too, with a four flash array helping better accentuate natural skin colours while a flicker sensor works against flicking indoor lights for better party snaps.
Although Apple now offers a dual-lens snapper, this has been reserved for the 7's big brother, the iPhone 7 Plus.
iPhone 7 vs iPhone 6S software: Nothing to separate the two
Unlike Android updates which take an age to filter out between the hundreds of devices doing the rounds, Apple's iOS upgrades are a much cleaner, swifter affair. As such, on the software front, there's very little that will separate the two handsets.
Sure, the iPhone 7 will run the new iOS 10 update direct from the box whereas iPhone 6S owners will have to download it manually - hardly the most strenuous of tasks - but once installed it should create a level playing field.
None of the already confirmed iOS 10 features - we're talking improved Siri functionality, smarter Photos tagging and search, and the ability to sniff out and warn you about potential spam calls - are limited to one device. What's more, with the iPhone 6S on the iOS 10 compatibility list, there's no excuses for this not to be an even race.
iPhone 7 vs iPhone 6S battery: Staying power on the up
The iPhone 6S's battery life is decent without being groundbreaking and, but the iPhone 7 has been on the receiving end of a bit of a staying-power boost. Those hopes of a phone that will last weeks not days are still misplaced, though - expect an extra two hours life from a single charge though.
Is it the biggest update set to be bestowed on Apple's next-gen blower? No, but it's nothing to be sniffed at either. That extra hour could be the difference between enjoying a bit of a Facebook sesh on your way home after a night out.
iPhone 7 vs iPhone 6S price: Expensive or expensive?
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No matter which route you take in the iPhone 7 vs iPhone 6S battle, you're going to want to put a serious chunk o' change aside because neither of them are particularly cheap.
Although having been handed a sizeable price cut, the iPhone 6S still isn't what you'd call affordable. Available in two capacities, the 32GB iPhone 6s will hit you for £499 while the 128GB until will set wannabe owners back £599.
By contrast, those after the iPhone 7 will need even deeper pockets. Here there are three storage options, will the entry point 32GB coming in where the 6S caps out with a £599 fee. Need more space? Fine, be warned though, the 128GB and 256GB models cost a lofty £699 and £799 respectively, ouch.
iPhone 7 vs iPhone 6S: The summary
The iPhone 7 isn't the biggest update in Apple history. Like Apple somehow always manages though, it offers just enough to get you excited and coveting an upgrade. If you're due an upgrade and can afford it, the iPhone 7 is the handset to go for. Already got an iPhone 6S though? You're probably better off sticking with it than forking out a significant sum on minor improvements.