With all the top smartphones in the world boasting their quad-core processors and Full HD displays, it's harder and harder for an individual to really stand out. With the Xperia Z, Sony made a brave attempt at differentiating by waterproofing the phone so you can spill beer on it without it giving up the ghost.

The Xperia Z1 keeps its liquid-repelling credentials, along with sexy glass design and Full HD screen. Its quad-core processor has been supercharged to 2.2GHz, and its camera now boasts an impressive 20.7 megapixels.

There's no word yet on exactly how much Sony will demand for this high-spec beast, but it's safe to assume that it'll be roughly on a par with the Xperia Z. Don't expect to pick it up for any less than £500 when it goes on sale in the UK in the coming few weeks.

Design

There's no question that the Z1 is the successor to the Xperia Z. With the all-glass front and back, the family resemblance is striking. Throw in the sleek Xperia branding on the back, the camera lens in the top-left corner, and the rather large power button on the right-hand edge and you'd be forgiven for mistaking the two.

There are differences, though. Chief among them is the aluminium band that now wraps around the edge. It's milled from a single piece of metal that Sony reckons makes it stronger. It certainly makes it more comfortable to hold. The previous model had a bit of a sharp edge to it, but the rounded metal on the Z1 feels much nicer, not to mention more luxurious.

It has roughly similar dimensions to the Z, but it's marginally thicker. Although both the Z1 and Samsung Galaxy S4 have 5-inch displays, the Z1 is slightly longer and wider than Samsung's phone. You still won't struggle to cram it into your Levis, but if you want a compact phone to wrap your hands around, you might want to look elsewhere.

Like the Xperia Z, the Z1 is completely waterproof. You can submerge it in water to a depth of 1.5 metres for up to 30 minutes. If you've destroyed a phone by dropping it in the toilet -- or by making calls in the rain -- the Z1 might be the phone for you. It keeps water out by sealing its ports with smaller flaps. While the Xperia Z placed a flap over the headphone jack, the Z1 has simply made the jack itself waterproof, meaning you don't need to undo it every time you want to plug your headphones in.

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Display

At 5 inches on the diameter, the screen stays the same physical size as it was on the Xperia Z . The Full HD resolution remains the same as well, although Sony reckons the display has seen an update.

At a hands-on event, it boasted that the phone now uses the same Bravia technology found in its high-end TVs that boast rich colours, deep contrast, and pin-sharp clarity. I wasn't able to bring up CNET's usual set of screen test images and videos, but it certainly looked pretty good. The older Z had a great screen, though, so the Z1 has a lot to do if it wants to beat its predecessor.

Processor and software

Stuffed inside that glass and metal body is Qualcomm's latest Snapdragon 800 quad-core processor, clocked at an astonishing 2.2GHz. The Galaxy S4 currently sits proudly around the top of the phone power league, but that has a slightly slower 1.9GHz chip.

I wasn't able to run our usual set of brutal tests to see exactly how the two measure up, but it's safe to say that the Z1 is going to be a powerful beast. To help keep it chugging along, Sony has whacked in a capacious 3,000mAh battery.

It's running on Android 4.2.2 Jelly Bean. That's not the latest version of Google's mobile software -- that's 4.3 Jelly Bean -- but with Sony's cosmetic changes, you probably won't tell much difference. It has the same basic functionality of Android with multiple home screens, but you're able to easily change the order of your app icons in the menu to quickly show most-used apps or custom order.

The image and video galleries have been replaced, too, and Sony has lumped in its Music and Video Unlimited streaming apps. While these are paid-for services, you will get 60 days of music streaming for free as well six free "blockbuster" movies, including "Elysium," as soon as it becomes available as a digital download.

Camera

Probably the most exciting update to the Z1 is the camera, which now boasts a whopping 20.7 megapixels. That's a significant jump from the 13 megapixels of its predecessor, but Sony says that there's more than just a megapixel bump going on.

The sensor size, at 1/2.3-inch, is bigger than what you'd find on your normal smartphone and is similar to the Samsung Galaxy S4 Zoom's (1/2.33-inch). In comparison, the iPhone 5 uses a small 1/3.2-inch sensor, and the HTC One's UltraPixel sensor is slightly larger at 1/3-inch. The Nokia Lumia 1020 has the biggest sensor at 1/1.5-inch for smartphones running a modern OS.

The Z1 also uses a wide angle 27mm f/2.0 G Lens, and Sony claims that its Bionz image processor has been tweaked to minimize noise in low-light environments.

As can be seen in the sample shots below, the performance of the prototype unit for outdoor shots seemed average at best, though low-light performance was definitely much better compared with those from the Samsung Galaxy S4 . The large pictures captured with the 20.7-megapixel sensor does mean you can capture a lot more details, though the average picture size (at 3.6MB) will be a concern for anyone who wants to take a lot of pictures. Color performance was also pretty accurate.

Aloysius Low/CNET

Aloysius Low/CNET

Aloysius Low/CNET

We didn't test Superior Auto mode because the software wasn't yet finalized.

There's new camera software, as well. You can load new apps directly in the camera, letting you perform neat tricks without having to switch between different apps. There are four onboard as standard -- including a burst-mode that lets you select the best shot from 61 photos and an app that lets you live-stream video to your Facebook page. Sony says it's working with developers to bring more apps. There's also the usual array of scene modes as well as sweep panorama and HDR modes.

Outlook

With its Full HD screen and waterproof design, Sony's Xperia Z was already a great phone, particularly for those of you who are quite clumsy or live on boats. The addition of the aluminium band makes the Z1 both look and feel like a more luxurious product, while the beefy processor and supercharged camera should make it a top performer in all respects.

CNET's Aloysius Low contributed to this report.