Several operating system platforms, including Windows Mobile, Symbian and the Palm operating system, are battling it out in the nascent smartphone market. While the Palm platform isn't a major player in most of the world, a recent report by the NPD Group places it as the leading smartphone platform for the third straight month in the United States.

According to NPD, Palm OS smartphones this March exceeded Microsoft and Symbian Series 60 market share combined. NPD's data on the U.S. smartphone market gave the Palm OS a 47 percent market share, an increase of 13 points from January. Microsoft (the combination of Pocket PC Phone Edition and Microsoft Smartphone) and Symbian Series 60 tied with 20 percent market share each. Series 60 is the most common type of smartphone based on the Symbian platform.

NPD said rising sales of the Treo 600 smartphone from palmOne and continued success of Kyocera and Samsung Palm OS smartphones contributed to the Palm platform's success.

Of course, worldwide, it is a different matter entirely. For instance, Gartner recently reported that Symbian saw global shipments of handsets based on its platform doubled to 2.4 million in the first quarter of this year over the first quarter of 2003.

According to Gartner, in 2003, more than 6.67 million smartphones based on the Symbian OS were shipped worldwide of a total of about 10 million smartphones sold. That leaves other platforms, such as Windows Mobile, the Palm OS, BlackBerry and Linux, to fight over the rest of the market.

While this is a drop in the bucket compared to the over 520 million mobile phones sold worldwide last year, the overall sales of smartphones are expected to grow exponentially over the next few years. ABI Research predicts Symbian will ship on almost a quarter of all handsets by 2009. That's in a market that should top 600 million units.

Symbian has a lot of competition, especially for arch rival Microsoft, which has started to make some headway with its Windows Mobile operating system. Research and consulting firm ARCchart predicts that PC and PDA vendors could swing the smartphone market in Microsoft's favor. If the PC and PDA vendors do enter the market, ARCchart estimates that by 2008 it would cut the Symbian operating system's market share lead to just 8 percentage points above the Windows Mobile for Smartphone platform, giving Microsoft an overall 33% market share of smartphones.

So where does all this leave the Palm platform's dominance in the relatively small U.S. market for smartphones? It gives the company important mind share among consumers, as the U.S. market for smartphones could be huge one day. And if PalmSource and its licensees can continue to churn out products that satisfy customers, but with more variety and price ranges, the Palm platform has a chance to maintain a good percentage of the U.S market as it grows. Gaining traction in Europe and the rest of the world, where other platforms are more estanbled, will prove more difficult.