Ah, the old iOS versus Android debate. Which is better? No one can say for sure. Not categorically anyway. These two leading mobile operating systems are just too good in too many distinct ways.
It's a little easier to make a judgement call when comparing the iPhone 6 and the Samsung Galaxy S6 interfaces, because Samsung does insist on layering its own inferior software modifications over the perfectly fabulous Android 5.1.1 Lollipop.
Google's Android 6 Marshmallow update is beginning to roll out to the Galaxy S6, but it's taking some time to hit the major markets. Plus when it reaches the UK and US we will also need to wait for networks and carriers to release the update to customers.
With Android Lollipop the Korean manufacturer has pulled back from its irritatingly meddlesome ways to a fairly significant degree. TouchWiz remains difficult to love, but it also stays out of your way far more than before.
You still get the sluggish, pointless Flipboard-powered magazine view when you scroll to the left of the main homescreen, and the settings menu is still a bit of a mess of gaudy toggles and options.
But there's less bloatware, fewer sluggish animations, and a generally cleaner, leaner look and feel to its icons and menus. You get a fairly classy little clock widget overlaying the main homescreen rather than the stick-out-like-a-sore-thumb widget of yore.
You still get the best features of Android 5.1.1 here too, and almost unfiltered at that. Multitasking adopts Google's slick, endless carousel approach (which also splits up individual web tabs), while the power and clarity of the notification system still knocks iOS 9's vague approximation into a cocked hat.
The iPhone 6, of course, comes with iOS 9 (it originally launched with iOS 8) unfiltered. There is no other kind of iOS 9. It's one of the biggest strengths of Apple's ecosystem - there's no clunky elaboration from manufacturers who think they know better.
It's also just a simple pleasure to use. Despite the major aesthetic overhaul Apple brought about with iOS 7, and the major enhancements added in iOS 8 (many of which are lifted from Android), this is still at heart the same iOS that defined the smartphone industry back in 2007.
iOS 9 brings improvements to Siri, adds transit directions to Apple Maps, tweaks the keyboard and more.
This means that using the iPhone 6 won't thrill or excite you, but it also means that it feels instantly familiar and dependable. It trades novelty and freshness for well-honed functionality, which is precisely why it's such a hit with those who don't trawl tech blogs for the latest news and reviews every hour of every day.
Where Apple has embellished its operating system over the years, it's almost always been thoughtfully executed and well integrated. Control Centre is a case in point. At heart, Apple's drag-up menu is similar to the options presented in the drag-down Android menu, offering instant access to things like Wi-Fi, Bluetooth, screen brightness, and a bunch of handy tools besides.
But it just feels that bit slicker and more intuitive here, not crowded in with a load of other toggles and functions. It's something I use an awful lot, whether setting a timer for some cooking pasta, fumbling to find my front door lock in the dark (thanks to a handy torch function), or blearily flicking into airplane mode for the night.
If there's a learning curve to the iPhone 6's operating system, then, it manifests itself at the gentlest of angles.
Performance across these two phones is uniformly tight. There isn't a single task or app that stretches either, it seems. 4K video, 3D gaming, photo editing - all are handled with consummate ease.
However, the Galaxy S6 is undoubtedly the more powerful device in purely technical terms. Its Exynos 7420 CPU is an octa-core (in effect two quad-cores) chip clocked at 1.5GHz. That compares favourably to the iPhone 6's A8 chip, which is a dual-core 1.4GHz example. The S6 also has three times the RAM of the iPhone 6 at 3GB.
Of course, Apple's custom approach to processor tech yields results that frequently exceed the best that the Android crowd can manage with their off-the shelf parts. That's particularly the case with single-core performance, which still plays an important role in most smartphone tasks.
However, Samsung has also gone the custom route with the S6's chip, and it's produced a stunner. In my Geekbench 3 benchmark tests, the iPhone 6 was only slightly faster in single core terms (scoring just 100 points higher on average), while the S6 was massively faster in multi-core terms (2300 more on average).
This is actually pretty meaningless, though, thanks to the vastly different operating systems each runs. Android and iOS utilise processors and memory resources in completely different ways.
In practical terms, then, both phones are as fast as they get for their respective platforms - and that's all that you really need to know when making a decision between the two.
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