Here's what we think of the new Android heavyweight.
Samsung Galaxy S4: Design and build
The Galaxy S4 looks something like a cross between the Samsung Galaxy S3 and the Galaxy Note 2. It comes in 'black mist' and 'white frost' colours which look pretty standard but still stylish. We understand that other colours will launch later on in the year.
Despite the fact Samsung has stuck with the same flimsy plastic rear cover found on the Galaxy S3, the design of the Galaxy S4 is impressive. This is mostly because the firm has managed to put a larger screen into a slightly smaller handset, compared to the S3. It's an impressive feat and means the Galaxy S4 doesn't feel unwieldy in the hand. It's both thin and light at 7.9mm and 130g.
The device feels more solid than the Galaxy S3, but the plastic build is a downfall of the Galaxy S4, it can't compete with the likes of Apple, Sony and HTC in this area.
There are a couple of caveats other than the build quality to mention. The first is a minor niggle in that the front of the handset is interrupted by the front facing camera and three sensors, most noticeable on the white model. The other is that the touch sensitive buttons below the screen which sit either side of the physical button are a) difficulty to reach and b) get pressed too easily due their close proximity to the edge of the device – namely the back button if you're right handed.
Samsung Galaxy S4 video review
Samsung Galaxy S4: Hardware
There's no faulting the Galaxy S4's hardware which rivals devices like the HTC One and Sony Xperia Z. It's a shame that the UK model comes with a 1.9GHz Qualcomm Snapdragon 600 quad-core processor instead of the Exynos octa-core chip. Nevertheless, the Galaxy S4 is no slouch of a phone.
With a whopping 2GB of RAM the Galaxy S4 blasted through our benchmarks as we expected it would.
It breezed its way to being a new record holder in both Geekbench 2 and GLBenchmark with results of 3227 and 41fps. The former is significantly more than the HTC One's 2721 previous record and almost twice that of the Galaxy S3.
The Galaxy S4 couldn't quite manage a treble win but still gave us an impressive time of 1092ms in the SunSpider test. The iPhone 5 remains the best phone in this area at 903ms.
However, at the end of the day these are just numbers and you can get excellent performance from similar hardware for less money in the HTC One and Sony Xperia Z. Even with outstanding benchmark results, we found the Galaxy S4 occasionally laggy when opening certain apps.
Once again, storage is an iPhone matching 16GB, 32GB and 64GB and Samsung has gladly kept the microSD card slot for expansion. This is an area where Samsung has one up on many of its competitors, namely the iPhone 5 and HTC One.
However, as others have found, the device comes with a large chunk of the storage space already used up. Our 16GB model had just over 9GB of free storage which is much less than we are accustomed to finding. The microSD card helps but you can't install apps here so it makes for a tricky situation.
The 5in Full HD screen on the Galaxy S4 is really impressive. The SuperAMOLED technology means colours are vibrant but not over the top like previous models. It matches the Xperia Z's pixel density of 441ppi meaning the HTC One is still the highest at 469ppi – a minor difference. Samsung says it consumes less power than the Galaxy S3's display which we hope is true.
Samsung Galaxy S4: Software
As you might know, the Galaxy S4 will ship with Android 4.2 Jelly Bean. The interface is familiar to that of the Galaxy S3 so existing Samsung users will feel right at home. Other Android users shouldn't find it too hard to get used to either, since everything is located where you would expect it to be.
One tweak is that the settings menu has been split into different tabbed sections, but this isn't hard to get accustomed to. As well as the Google Play Store, the Samsung Hub is another source for games, movies, music and books.
What Samsung offers is seemingly endless amounts of software features on top of the usual Android ones. The firm did this with the Galaxy S3 to differentiate itself and has gone even further with the Galaxy S4. Since there are so many we'll go through each one, explaining what it does and whether it's any good.
Air View and Air Gesture
Air View and Air Gesture are innovative screen technologies. The former lets you can preview information by hovering a finger above the screen while the later means you can scroll through content or answer the phone with a wave of your hand. They work reasonably well once you get the hang of it and could be handy, albeit in a few niche situations such as when you're cooking and have messy hands.
Smart Scroll and Smart Pause
Samsung has also advances its Smart Screen technology with the Galaxy S4. Smart Scroll and Smart Pause are two new features which utilise the front facing camera. They allow you to scroll up and down pages and pause video content without touching the screen.
We found the automatic scrolling of Smart Scroll buggy and hard to use – apparently it doesn’t work too well if you wear glasses and it often scrolled when holding the phone at a suitable viewing angle. When it does work, it's a neat thing to show off in the pub but we can't see a real-life use for it apart from being extremely lazy. It also doesn't work if you're using the Chrome browser or Gmail which is a shame.
We can see that automatically pausing a video if you look away from a screen is cool but pretty handy too, the problem is a slight delay before it happens and a weird sensation where you don't know if the handset has done it properly or not. The feature works with your own videos and apps like YouTube.
One of our favourite features is Multi window. This allows you to use two apps side by side in a similar way to Snap Views in Windows 8. You can have a straight 50:50 split or let one app take up more real estate than the other to varying degrees. It works in both portrait and landscape but an annoying retractable side bar stays put unless you switch the mode off.
S Translator and S Health
Two key apps which Samsung pre-loads onto the Galaxy S4 are S Translator and S Health. The S Translator helps you communicate either by text or speech recognition with someone who doesn't speak your language. It works pretty well but there are only eight languages aside from English plus it needs a data connection to work which isn't handy when you're abroad and roaming.
For those into fitness gadgets, the Galaxy S4 is one in itself. With its multiple sensors and S Health app you can keep track of your steps, calories used and other information.
Like the HTC One, the Galaxy S4 can be used as a TV remote control because it has a built-in infrared sensor. It's a handy way of controlling your TV if you've lost the remote and also works for multiple devices in rooms around the house. Furthermore, it tells you what's on the box and gives recommendations. Compatibility will vary between devices and you might not get all the functions working. At the end of the day, reaching for the dedicated remote is still easy, if far more boring.
Overall it's a mixed bag when it comes to these software features. Many seem to be there for the sake of it, to have bragging rights but no real day-to-day benefit to the user. However, some are really handy.
Plenty more software features appear in the camera app which we'll talk about next.
Samsung Galaxy S4: Cameras
The Galaxy S4 has a 13Mp rear facing camera and a 1.9Mp front facing camera and both images and video footage from each was very impressive with excellent levels of details, good exposure and colour saturation on the default 9.6Mp (16:9) setting.
When not being used so heavily, the Galaxy S4 holds it charge well when in standby so lighter users can expect a couple days use from the phone. We got through 24 hours and lost just over half of the battery, the screen sucked up most of the power .