Updated: read our Hands on: Sony Xperia S review.

The arrival of the Sony Ericsson Xperia Arc S illustrates how incredibly fast things are moving in the world of Android hardware. The original Xperia Arc launched in April, now here's the upgrade a mere six months later.

Well, we say "upgrade"... what you're getting in the Sony Ericsson Xperia Arc S is two new features that aren't in the older Arc - a faster 1.4GHz single-core processor, plus the latest Android 2.3.4 update of Google's operating system and Sony Ericsson's user interface skin.

And even then, the 2.3.4 software update is scheduled to arrive as an over-the-air upgrade for the first Xperia Arc this month, meaning that the only real new thing here is the faster processor.

In terms of price, the original Sony Ericsson Xperia Arc has seen its RRP aggressively trimmed to a point where it's available unlocked for well under £300. The Sony Ericsson Xperia Arc S nearly matches that, coming in at £299 unlocked if you shop around, or on monthly contracts starting around the £26 level.

Sony ericsson xperia arc s

For those prices, the Sony Ericsson Xperia Arc S is a heck of a lot of phone. For a start, the screen is the same extra-large, 4.2-inch Bravia Engine Reality Display as found in the original Arc, which is one of the finest, brightest, sharpest and most responsive touchscreens around today.

Sony ericsson xperia arc s

Running at a resolution of 854 x 480, the screen is definitely the highlight of the Sony Ericsson Xperia Arc S. And it's been squeezed into an incredibly thin, flared chassis, which is slimmer around its waist and slightly fatter at the ends. This makes it feel impossibly thin in the hand. It's a lovely design.

Sony ericsson xperia arc s

One of the few complaints we had in our review of the first Sony Ericsson Xperia Arc was that its teeny-tiny power button was rather hidden away in the top corner of the phone, and so deeply recessed it was hard to find.

Sony ericsson xperia arc s

Now, this may be a manufacturing tolerances thing, but the power button on the Sony Ericsson Xperia Arc S sticks out a tiny, tiny bit further, making it that little bit easier to find. But that might just be because it's new and rigid.

Sony ericsson xperia arc s

The rest of the phone is physically identical to the first Sony Ericsson Xperia Arc. The back houses the HD camera sensor, LED flash and secondary noise-cancelling microphone, with the white finish of this particular model having a slightly mottled enamel look to it.

Sony ericsson xperia arc s

The right-hand side of the Sony Ericsson Xperia Arc S houses the USB connector at the top, a small volume up/down rocker that would benefit from being a little larger and more prominent, plus down at the bottom sits the camera shutter button.

Sony ericsson xperia arc s

It's a nice two-stage button, with a double level press - one to focus, another to shoot. Again, it's a little too small thanks to the extreme thinness of the Sony Ericsson Xperia Arc S, but it's sensitive enough to make taking photos straightforward.

Also, holding it down wherever you are in the phone's menus boots up the camera.

Sony ericsson xperia arc s

The top edge houses the power button and HDMI connector (but there's no HDMI cable in the box), plus you can see the proximity sensor that deactivates the screen when you're making a call. Rather oddly, the Sony Ericsson Xperia Arc S doesn't feature a front-facing camera. Just like its predecessor.

Sony ericsson xperia arc s

Navigation buttons are physical, with Sony Ericsson continuing to not bother with Search, giving users Back, Home and Menu. They're very low down on the phone, which can make it feel a little top heavy in the hand, but it's a compromise worth making in return for having such a whopping screen and slim case, as far as we're concerned.

Sony ericsson xperia arc s

So yes, it's basically the exact same physical size and shape as the first Sony Ericsson Xperia Arc, which means it's still one of the slimmest, sexiest and all-round loveliest gadgets you can buy today - plus available at a much lower price than many dual core offerings.