Its resolution does mean that everything looks absolutely pin-sharp. Icon edges and small text are extremely crisp, making it comfortable for reading long pages of texts. In terms of clarity, there's little difference between it, the standard S4 or indeed its other Full HD rivals, the Xperia Z or.
Android 4.2.2 Jelly Bean
The Active comes running Android 4.2.2 Jelly Bean which is currently the latest version of Google's mobile operating system available -- although version 4.3 is on its way soon. Version 4.2.2 is the same software you'll find on the standard S4 too, so don't worry that you're being lumped with a substandard version.
The core interface is the same as the S4 and indeed the smaller S4 Mini. There's five homescreens to load up with apps and widgets, with a grid of apps for anything you don't want right at the front. Navigation is done using the physical buttons at the bottom -- pressing and holding the middle home button brings up the multi-tasking carousel.
In true Samsung fashion, the Active has been loaded up with a boatload of extra software features. Air Gesture allows you to swipe through photos or web pages just by waving over the phone. Normally I'd say this was a gimmick, but it'll come in handy when you're outside caked in mud.
Other S4 features are on board like Smart Scroll (scroll through pages by tilting the phone), Smart Pause (video will pause when you look away from the screen) and Smart Stay (screen won't time out when you're looking at it). I wasn't super excited about them on the S4 and I'm still not here. They're fun to play with, but can often be frustrating. I definitely wouldn't miss them if they weren't here.
One tool that is quite handy is the ability to show two apps on screen at once. It's really helpful to be able to have a notes app open, for example, while checking information on a web page. The exercise and food tracking app S Health is on board too, as is the translator tool.
There really is a whole lot of extra stuff loaded onto the Active, which, if you spend the time trying to understand it all, can be quite fun to play with. Much of it is pretty pointless, however, and just makes the phone much more complicated to use. There are duplicate app stores, email clients and web browsers, while the settings menu is so complex it's had to be split into four tabs. If you're a new Android convert, this is not an easy phone to get to grips with.
Processor and performance
Stuffed into the waterproof shell is a quad-core Qualcomm processor clocked at a meaty 1.9GHz processor. That's the same processor found in the standard S4, which gave the best results on my benchmark tests I've ever seen from a mobile device. I therefore expected big things from the Active.
What I wasn't expecting was for it to give even higher scores. While the S4 achieved 3,087 on the Geekbench test, the S4 Active sailed past to 3,230, which it maintained over multiple test runs. That makes it the most powerful phone I've ever tested, giving very real competition to some laptops.
By comparison, the HTC One achieved around 2,500, while the Xperia Z sits around the 2,000 mark. They're both fine scores, but the truly dedicated geeks among you will want to opt for the Active in order to put the dominant beast in your trousers.
Unsurprisingly, the Active was extremely swift to use. There's zero delay in swiping around the homescreen or when opening apps. Full HD video plays easily and editing high-resolution photos in Snapseed was very nippy. Demanding games like N.O.V.A 3 played with very high frame rates, resulting in smooth and enjoyable gameplay.
Do bear in mind though that that level of power is arguably overkill. Last year's Galaxy S3 still performs incredibly well even with the more demanding tasks, while the S4 Mini (1,875 on Geekbench) was swift and very responsive in my recent review. Such high performance might help in boasting to your mates, but it's not essential when it comes to actually using your phone.
The Active is powered by a 2,600mAh battery, which is the same size that you'll find in the S4. Unsurprisingly, I found both phones to have fairly comparable battery life.
Samsung reckons you can squeeze 8 hours of Internet browsing time over 3G from the phone, which I'd say is a little ambitious. As always, manufacturers will quote a best-case time, so this figure will likely have been achieved in ideal conditions with screen brightness at its minimum, and with GPS, Bluetooth and anything else possible turned off.
If you have the screen brightness turned up and are perhaps streaming music in the background, you can expect this figure to drop dramatically. As a general rule of all smart phones, you should expect to charge it every night. If you're a fairly heavy user, sending texts and emails, browsing the web, streaming music and so on, you'll probably want to give it a boost at lunchtime if you want enough power to keep going at the pub later in the day.
Stuffed into the back of the Active is an 8-megapixel camera. That's a sizeable step down from the whopping 13 megapixels of the standard S4. Megapixels aren't everything though, so I took it out into the delightful sunshine to see how it compares.
On my first shot of London's iconic Elizabeth Tower, the cameras gave quite different results. The Active's shot was darker than the standard S4, with warmer colours. The S4's extra pixels, however, mean the picture is much more detailed when you look at it full-screen.
On my second shot of this pigeon, the Active struggled to achieve a sharp focus on the bird. I took several shots of it and this was the best one I was able to get. While I had a couple of bad ones from the S4, the majority were in sharp focus. Overall exposure and colour reproduction is basically the same though.
Finally, both cameras did a good job of exposing for the bright blue sky while also keeping detail in the shadowy areas of this hut's brickwork and the grass in front. Again, the extra resolution of the S4 is clear to see in the fine detail on the brickwork.
While the Active's camera might not have the same grunt when it comes to pixels, it's perfectly capable of capturing a well-balanced shot with rich colours. It's more than good enough for some Facebook and Twitter snaps and if you take the time to set the scene properly, it could even help get some much more artistic shots too.
Samsung has thrown in a whole heap of camera software too. As well as the standard HDR and panorama modes, it's also lumped in the animated photo feature (allowing you to selectively animate a portion of a moving picture), Best Face (take multiple pictures of a group of friends and select the best faces individually to merge into one shot) and plenty of others. The only feature from the S4 that's not on this camera is the ridiculous Dual Shot, which I'll miss about as much as I miss having the flu.
The Samsung Galaxy S4 Active is fatter than its sibling and its screen doesn't have the same eye-popping richness. It does, however, have a great camera, a Full HD resolution display and a searingly powerful processor. The waterproofing is a brilliant addition, giving peace of mind when using your £500 phone in the rain. Unless you're desperate for a paper-thin phone, I'd recommend this over the S4.