If you think of the HTC Advantage purely as smartphone, you're talling one hefty bit of kit - so big in fact that it comes in two parts. Weighing in at over 359g, the device sets some sort of record for a smartphone.

However, if you make the mistake of comparing the Advantage to an ordinary mobile, or even to most pocketable PDA phones, then you are probably missing the point. Think of it as a tablet-style laptop that you can actually fit into a coat pocket then you are getting closer to what HTC is attempting here.

The HTC Advantage (also available in network operator-branded guise as the T-Mobile Ameo) is essentially a Pocket PC-style device, running Microsoft's Windows Mobile 5.0 Pocket PC Phone Edition operating system.

But what makes this beast rather different from other smartphones and palmtops running the same software is the size of the colour display. This touchscreen LCD measures a massive five inches across. It's big enough to comfortably watch television or downloaded movies on - and you could do just thanks to its combination of communication technologies and memory capabilities.

The device ticks all the right boxes when it comes to connectivity as it provides fast access to data and downloads on the move thanks to 3G access, and offering low-cost hook-ups using Wi-Fi when you have one in range.

Just as importantly the phone does not make do with the usual paltry onboard memory and card slot of many of its rivals. Sure, you can use a MiniSD card (a quick way of getting files on and off the phone), but it also has an 8 gigabyte harddrive.

The piece de resistance, however, is probably the built-in GPS antenna. Sure we have seen plenty of phones with satellite navigation as standard.

But this not only offers the reassurance of maps and instructions from market leaders TomTom - it also has that advantage of the huge screen. When it comes to seeing where you are and where you need to go, it pays to have an LCD where you don't have to squint.

The main part of the phone is a chunky 280g device with little more than the screen to show. There are fastkey buttons for getting the Start menu or for firing up the web browser, and there is even a small but useful joystick control to use for navigation and selection should you so choose.

However, the absence of more substantial or more numerous buttons is down to the fact that you use the stylus for touchscreen control, like a miniature mouse to access pop-up screens, scroll through menus and decide what feature you want to activate next.

The second part of the Advantage is the keyboard. This is not hidden away in some sliding drawer arrangement, or behind some discreet hinged panel. The Qwerty console is completely separate - and at 70g weighs more than some whole mobiles.

The ingenious part of the two-part device is that there are no cables to connect, or even any Bluetooth to activate. The two halves simply slot together through magnetic attraction. The magnetism is strong enough to hold the heavy screen at a 110° slant to the keyboard as it sits on the table. The electrical connection and physical bond is made with no alignment fiddling or fuss.

The phone is supplied with a smartly-designed folder-style case into which the main unit is held in by two side arms, and the keyboard is secured again using magnets.

You don't actually need the keyboard in order to type. There is an option of a virtual onboard keyboard or a choice of three different character recognition systems that will typeset your handwriting. But for the average PC user, a more usual set of keys to type emails or write documents is a real plus. The keys by smartphone standards are large and well-spaced, allowing you touch type at a reasonable speed.

You get the usual suite of cut-down versions of Excel and Word - but the difference here is that the screen is large enough to make editing spreadsheets on the move (rather than simply trying to view them) a real possibility. The Powerpoint viewer is also greatly enabled by huge viewing area.

Most users, however, will probably spend more of their time trawling through web pages than producing documents with this device. Again the sensibly sized screen is a huge advantage - and there is a choice of Internet Explorer or Opera to use as your browser. Both will work with the onboard VueFlo system that allows you to scroll through pages simply by tilting the screen.

The large screen does not benefit every operation, however. The Advantage has a 3-megapixel camera - and has a good quality autofocus system that allows you to focus sharply on subjects that are just a couple of centimetres away from the lens.

Pictures are pretty good compared with many camera phones. Colour rendition is not perfect, but lowlight performance is good, and there is the benefit of a flash light when you need it. But the trouble is that the screen is just too big to use as the camera viewfinder - making picture-taking in public an embarrassment.

Making phone calls could also be similarly ill-fated; however, the phone is sensibly set up for speakerphone use, rather then for ear-and-mouth contact. A set of headphones with a standard 3.5mm plug are supplied for use if you want a touch more privacy with your calls.

A set of stereo Bluetooth headphones is also an option - and a sensible one if you are to take advantage of the phone's reasonable MP3 capabilities.

Sounds and videos are played back by Windows Media Player (although you could upload different software, such is the beauty of a smartphone) - and the harddrive space means that although this won't rival the song capacity of an iPod Classic, it can save away a fair few tunes.

If you are willing to accept that the Advantage makes a more meaningful alternative to a laptop than a smartphone, then perhaps HTC is on to a winner. The screen and raw strength of this device make is more than capable of serving as a portable office.

Not surprisingly it is not a low cost option - coming in at £550- £600 SIM free (although it can be bought with a contract from T-Mobile as the Ameo).

In truth, though, we can't imagine many people being converted to this hybrid product. Size may not be everything but if you are a portable or pocket product, then it sure does count for a lot.

Words: Chris George

Looks 7

Ease of use 8

Features 9

Call quality 8

Value 7

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