The MP3 player, written by Emuzed, works well enough, but the SX1's limited on-board RAM - just 4MB - means a memory card is essential. Video playback is handled by PacketVideo's recording/playback app, which grabs 176 x 144 footage in 3GPP format. Around 22 seconds of video with mono sound will occupy just over 200KB of memory, and the quality's (7.5fps) not bad. Siemens also bundles Real Network's RealOne Player, though it's arguably redundant.

For still photos, there's the usual camera app, Snapshot, and album viewer, Images. Image Fun, meanwhile, provides some basic image manipulation tools. A necessary adjunct for a business-oriented phone? I doubt it, but with smart phones increasingly appealing across the board, Siemens is probably right to bundle such frivolous stuff.

Just as the MP3 player app exposes the SX1's paucity of internal memory, so Image Fun reveals the weakness of the handset's controls. Yes, it appeals to the eye, but the tiny chrome joystick is a pain in the neck to use. Positioned for to be moved with your thumb, the joystick's smooth curves make it almost impossible to nudge one way or t'other without pressing it down too. As with the camera and hands free buttons on the side of the handset, Siemens has given the joystick a low profile to avoid accidental knocks, but equally that also makes it hard to move correctly.

Since the joystick is not only used for navigating around the phone's UI and applications, but for controlling the speaker volume - I discovered this by accident; it's not at all clear from the handset which buttons you use - and other features, this is a real problem for any user who lacks the daintiest of fingers.

Ditto the numeric key array. After a few days' use, I started to get the hang of the SX1's keypad design, with numbers one to five down the left hand side of the screen and the rest down the right. Siemens' user research clearly suggests that folk dial using two hands and so the company has positioned the SX1's twin key arrays to be each operated by one of your thumbs. Fine. It does work that way. But try doing it one-handed when you're carrying a briefcase. It's possible but uncomfortable.

Texting is even trickier. That's partly because, used as I am to the more standard layout on my Nokia 6310i, I have a different mental map of the keys than the SX1 presents. But more to the point, it's bloody hard reaching over with your thumb to press a key the correct number of times to get the character you want, particularly those reached through keys 1, 2 and 3.

There is one benefit to the layout: it provides a series of buttons on either side of the display that can be linked to on-screen items in the same way that the two buttons on either side of the joystick correspond to the two action named at the bottom of the display. In a number of apps - selecting pre-set stations in the radio, for instance - this eliminates the need to use the joystick.

Had Siemens put the numeric keys where they are on 90 per cent of handsets, the SX1 would have scored rather more highly than it does. Design, we're told, is at its best when it's not obvious. Alas, Siemens seems to think that it's more important to offer a phone that will garner glances than one that's comfortable and convenient to use. It's by no means alone in holding such a view - Nokia has it to.

Otherwise, the SX1 was a joy to use. The display appeared slightly darker than the Nokia 6600's similarly sized equivalent, but was much easier to read with the backlight turned off. Its battery life is certainly better, but probably not much more than the bigger capacity (1000mAh to the 6600's 850mAh) yields. The SX1 definitely feels faster than the 6600.

Verdict

Dodgy keypad layout aside, the SX1 is never going to rival either the Treo 600 or the P900 for entering larger volumes of text than brief SMS messages. Siemens no doubt considers those phones as rivals, but they're really battling it out with each other, leaving the SX1 head to head with the 6600. Both are phones that offer a good deal of PDA functionality - the Treo 600 and the S900 are coming at the problem from the other end, as PDAs that have been shaved down to work as mobile phones too.

Which approach best suits you with depend on how you use your phone. For me, it's about voice communications and the ability to carry personal information around - my inbox is too full of spam for my phone to be a viable email platform yet. Out of the SX1 and the 6600, I prefer the former, despite being a long-time Nokia user. I could get used to the SX1's unnecessarily annoying joystick and weird keypad layout - the 6600's 'wading through treacle' speed, bulk and poorer battery life would be more difficult to acclimatise to. ®

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