Perhaps the number one killer of any mobile phone is its operating system. We've all made the mistake before. We get seduced by the hardware spec of a handset, teased by its touchscreen, mesmerised by the megapixels but after just 3 days of using the thing a bad OS can make you want to bring something heavy down onto it over and over again until a substance resembling guacamole comes out of its ports. The bottom line is that if a mobile's not a pleasure to use, it makes no difference how many codecs it supports, how pretty it looks or whatever other tricks it says on the box.

The Palm Pre isn't the world's sexiest looking phone. It's not unattractive by any means. Probably more akin to the phone next door as opposed to the sexy supermodel that is the LG Chocolate BL40. What we have known about the talk of this year's CES is that it's supposed to have staggeringly good software. The thing is that you'll have never used it before. No one will until they buy the thing because it's brand spanking new. So to help you agonise over whether or not the Pre's for you, here's a quick guide to its webOS and reasons for and against taking that leap into the unknown.

Probably an important place to start if this has all been gibberish to you so far. Since 1996, Palm devices have used the company's very own Palm OS whether they've been PDAs or smartphones. There's been the odd link up with Windows Mobile but on the whole it's been the old faithful. Palm's history has been fraught with takeovers, splits and mergers and, eventually, the software side of the company was sold to a Japanese firm from which the Palm OS was licensed back.

With the fresh start and new mass market charm offensive, Palm has decided do develop the software in-house once again to help create what the company feels is the perfect device - give or take a few tweaks for later iterations, naturally. It was with the handwriting recognition software, Graffiti, that Palm's founders initially began, so they've plenty of credentials in this department.

webOS itself is a Linux-based operating system but with Palm designed components on top of it. It gives it a rather curious mix of open source foundations and very effective proprietary guts at the same time, and the result is an agnostic way of integrating your social networks and other forms of communication. It's the default and entirely locked-in operating system for the Pre and will also be at the heart of the Palm Pixi which we'll probably see before the end of the year.

Being part Linux, part Palm specific, you might expect to have a few problems getting the Pre and webOS to sync up with your home computer and, unlike the old Palm PDAs, there's no HotSynch type function or cradle or anything like that. Instead webOS is designed to sync up with the cloud. It not only allows easy access to Gmail, Microsoft Exchange servers and Facebook but it'll also bring these messages together with all your communications with the same friends and colleagues on your phone contacts list. So, any conversations you've been having with any one person will all be threaded together in the same chat whether over e-mail, SMS or IM.

That's really the heart of Synergy with the idea to make using the phone as a seamless communicating device. It's not the only OS to do this kind of thing. Motoblur and HTC Sense aim for similar ends, but it's the simplicity and ease of use that's the selling point here.

Probably the biggest wow factor on the Pre is the graphic interface and the way it handles multitasking. Each application you use, and even the windows within them, become what Palm calls Activity Cards. These cards are displayed in a row on the screen whenever you press the touch sensitive main button on the handset. You can then shuffle through them, change their order and select the ones you want to work on with the multi-touch screen. And, when you're done with them, you can flick them off the edge of the screen to close them with a very satisfying kind of swish. Other OSes like Android and S60 allow multitasking but, so far, webOS seems to have provided the best most usable solution.

Again, it's another selling point for the Pre. The browser used is based on WebKit much like Chrome and Safari as well. With the aid of multi-touch and the browser works a treat allowing you to pinch and stretch and zoom your way in and out of the finer details at excellent speeds. Another big tick here.

webOS supports HTML 5, Javascript and CCS, so most parts of the Internet should run as they do on a computer. Adobe has also announced that they're working on Flash support for webOS which should fill in most of the important gaps - particularly in the way of embedded video.

webOS also features quite a neat search called Universal Search. When you start putting a search term into the field, it immediately starts presenting you with options. First of all it searches the handset for matches - anywhere on the handset - from your e-mails and texts to phone options, like where to turn on and off your Bluetooth. As it realises that what you're looking for isn't on the Pre, it'll ask you whether you want to begin searching the Internet as well.

webOS's ability to sync with iTunes has been a bonus but also something of quite serious contention between Palm and Apple. The phone gets by the Apple software by spoofing an iPod and coming up with ID protocols that iTunes recognises. There's been something of an arms race between the two companies - one patching the software and the other finding another way round it. It's up for debate as to how it will settle in the future but if this is a big point for you, then either don't update your iTunes software to version 9 or beyond or choose another phone. Naturally, the Pre has its own perfectly good media player which includes video support for codecs like H.264 but we all appreciate the desire to keep it the same and simple on the software front.

Yeah. Well, this is the one area currently letting the side down a little. webOS itself is set up very nicely to work with both first and third party apps. The trouble is that there aren't many. There's no need for developers to learn a new language to write applications for the Pre with just a one phone solution that's only been out in the States until now, it doesn't seem to have proved the most lucrative draw. Consequently, the Palm App Catalog, as it's known, only launched with 18 apps earlier this year and only features just over 40 today. Glaring omissions are Facebook, Skype and Flickr among many others, so it's really a question of how important apps are to you and how much you trust the Catalogue to grow in the future.

On the plus side, one of the available apps is called Classic and is an old Palm OS emulator which allows you to run tens of thousands of old school programs on the Pre either for nostalgia or hopefully because they've stood the test of time. There is also a growing community of homebrew apps which you can get access to through sideloading from your PC. There's a fairly healthy set of 250 or so at the moment but there's a good chance that many of them will be pretty rough around the edges.