You might think this will be an easy victory for the shiny, new Samsung handset. Even though the iPhone 4S wasn't the iPhone 5 we were hoping for, there's still plenty of reasons you might be swayed towards the iPhone over the S3.
Design and build
The two are very different specimens of smartphone. The iPhone 4S is a beautifully designed bit of glass and aluminium kit that sits nicely in the hand and will still look good 18 months into your contract. It does look a bit dated now though considering it's 9.3mm thick, chunky by 2012 standards.
The Galaxy S3 meanwhile is quite a bit bigger in size – including a 4.8in display. So while it might not be so comfortable for the small-handed gadgeteer when making calls, the pebble-inspired "Hyperglaze" finish on the skinny 8.3mm plastic body looks much more premium than its predecessor, the Galaxy S II. For now, we'll give this one to the iPhone 4S but it's really down to personal preference.
The iPhone 4S may have pin-sharp text and true whites on that 326ppi retina display but a 3.5in smartphone screen just isn't going to cut it anymore. Apple's been outdone by all the other big handset manufacturers on screen size and really needs to give us at least a 4in screen on the iPhone 5. The near edge-to-edge 4.8in Super AMOLED display on the Galaxy S3 is incredible. Hands down, the S3 wins on this round.
OS and features
Do you want the customisation available on Android Ice Cream Sandwich or the simple, rigid joys of iOS 5? The two operating systems have pilfered so much from each other (notifications, folders etc) that it's not TouchWiz but all the Galaxy S3's new features that are keeping the fight interesting.
There's S Voice to make sure your Siri-toting friends don't have the voice control advantage, Dropbox and (the incoming Android app) Flipboard pre-loaded as well as the eye-tracking feature Smart Stay which stops the screen from dimming when you're looking at it.
Out of the box, the Galaxy S3 seems like the best phone in the world right now for intuitive control but don't forget, the App Store has long been the jewel in Apple's crown – you can still do a lot more with an iPhone than an Android one thanks to all those third-party developers starting out on iOS. So for next-gen controls, choose the S3 but for the latest apps and games go for the iPhone.
Performance and camera
The iPhone 4S' A5 dual-core processor is enough of a performance boost for Apple fans to upgrade from the iPhone 4 but how can it compete with the quad-core innards of the Galaxy S3? Since Apple is known for optimising the performance of its chips due to the control it has over both hardware and software, this is more of a close call than you'd first think. In our brief hands on with the Galaxy S3, there wasn't one stutter when using apps, swiping through menus or using the camera – only an in-depth head-to-head review will do for this verdict.
Camera-wise, it's too soon to say which handset is the best. Both sport very impressive 8MP, 1080p video shooting snappers on the rear with the Galaxy S3 upping the ante with tons of features plus a front-facer with 720p video skills for HD Skype calls. We reckon this calls for lots of moody, low-light shots of the Stuff Office Cat.
On paper, the Galaxy S3 is the best phone in the world right now – not just the best Android phone, the best phone. The screen is glorious, the features are well thought out and that beast of a processor looks set to rip through anything we can throw at it.
But there will still be people who want an iPhone. Maybe they want an iPhone with a 4.8in, dazzlingly bright near edge-to-edge display, quad-core innards and nifty extras like automatically calling a contact if you hold it to your ear when reading a text.
The main criticism of the Galaxy S3 is that it's not an iPhone – but for everyone who can break free of Apple's hold (or never succumbed in the first place), the S3 looks set to be the phone of 2012.