SoftwareGoogle Nexus 4 - Android 4.2 Jelly Bean
Samsung Galaxy S3 - Android 4.1 Jelly Bean with TouchWiz UI
When the Samsung Galaxy S3 launched, it ran Android 4.0 Ice Cream Sandwich. However, the Jelly Bean update has now been applied, giving it the crucial speed boost that Google hardwired into the system's programming.
It's called Project Butter, and makes much more aggressive use of CPU power to give phones and tablets extra grunt when it's needed - such as loading apps and transitioning between parts of the interface.
The S3 lock screen
However, the Google Nexus 4 once again benefits from being that little bit newer, running Jelly Bean 4.2 instead of Jelly Bean 4.1. Some of the new features that 4.2 brings are included in the custom TouchWiz UI anyway, such as Beam - which lets you transfer files using NFC - but there are a couple of extra bits. Our favourite is a complete faddy frill, called Photoshphere. This is effectively a 360-degree panorama shot, letting you see your entire surroundings rather than just a slice.
Both the notifications menu and widgets have been given a tweak in 4.2 Jelly Bean too. The Samsung Galaxy S3 has its own share of extra bits too, though. One of the most headline-grabbing of the lot is the ability to play a video over the top of other activities - an extra bit of multi-tasking.
StorageGoogle Nexus 4 - 8/16GB, non-expandable
Samsung Galaxy S3 - 16/32GB (in UK), expandable
The Google Nexus 4 continues a relatively new trend in Android devices by not letting you expand the internal storage. There's no microSD memory card slot, making the choice between the 8GB and 16GB models all the more important. 8GB will only store around five movies at good SD quality, or a petite music library.
You have to pay £40 extra for the additional 8GB, which is an annoyance but certainly not a surprise. 64GB microSD cards can be bought for around £40 and 8GB cards for under £4. The extra space will come in extremely handy, though, especially when you consider that a chunk of the 8GB is taken up by the Android OS and its core apps.
The Samsung Galaxy S3 sticks to its geek guns, with at least 16GB of internal memory and a microSD slot hidden under the battery cover. This lets you boost storage into the stratosphere very cheaply.
32GB and 64GB editions of the Samsung Galaxy S3 exist too, although the 64GB version is not widely available in the UK. We'd advise opting for the 16GB edition and jamming in a memory card if you find you need more memory.
ConnectivityGoogle Nexus 4 - HSPA, Wi-Fi, DLNA, Bluetooth, NFC, MHL video output
Samsung Galaxy S3 - HSPA, Wi-Fi, DLNA, Bluetooth, NFC, MHL video output
The Google Nexus 4 and Samsung Galaxy S3 are evenly matched on connections, in that they include just about everything you could hope to have. The one thing missing is some form of HDMI video output, although the microUSB socket on both phones is MHL compliant, meaning with the right cable you can output video and surround audio to a TV. However, the Samsung Galaxy S3 demands you use the Samsung brand cable, although you can find cheapy knock-off cables if you don't want to spend the £15-20 the official cable costs.
Not too au fait with technical jargon? Other connection types include NFC and DLNA. NFC stands for Near-Field Communication and is a short-distance communication standard that can be used to transfer data. Its most exciting implementation is on the high street, though.
The Galaxy S3 MHL adapter
NFC can be used to buy low-cost items in certain shops. Generally it's used in food chains, such as sandwich purveyor EAT. It works a little like the contactless payment system now used by debit cards, requiring little more than a quick swipe.
Video playbackGoogle Nexus 4 - HD quality, Divx/MP4/H.264 support
Samsung Galaxy S3 - HD quality, Divx/MP4/H.264/MKV support
Samsung is renowned for packing excellent video support into its high-end phones - it has been going the extra mile on this front for years. As it runs stock Android, the Google Nexus 4 does not have any particularly impressive video skills.
The Google Nexus 4 has the power to handle just about any video you could fling at it, but it won't play back MKV files without a third-party app. The Samsung Galaxy S3 will. It's still one of the best mobile phone media players on the market. Expandable memory boosts its video potential too - with a 64GB in tow, you could store quite an impressive video library on the thing.
Patchy video support doesn't need to be a deal-breaker as there are plenty of half-decent third-party video players available from Google Play.
CameraGoogle Nexus 4 - 8-megapixel rear sensor, 1.3MP user-facing, LED flash
Samsung Galaxy S3 - 8-megapixel rear sensor, 1.9MP user-facing, LED flash
Specs-wise, the cameras of the Samsung Galaxy S3 and Google Nexus 4 are very similar. Both main sensors have eight megapixels a piece and both use an LED flash. The only difference is that the user-facing sensor is a little higher-powered in the Samsung Galaxy S3 - 1.9 megapixels instead of 1.3.
In practice, though, the Samsung Galaxy S3 is significantly better. Much like the video skills of the Galaxy S3, imaging is something that Samsung is good at, and it shows in the phone camera.
Of course, you do miss out on Photosphere, which is fun. However, there are apps available from Google Play that do pretty much the same thing.
VerdictIf you're after the best buy, the Google Nexus 4 is simply better value than the Samsung Galaxy S3 if you buy direct from Google. It's a cracking buy. Look into buying one on contract from a carrier and the argument is a lot less clear.
The Google Nexus 4 has a newer processor, more RAM, more up-to-date software and, in our opinion at least, a slightly better screen. However, for real power users, being able to increase the Samsung Galaxy S3's memory with a microSD card will be a huge benefit. Still, the Google Nexus 4 wins this fight.