Palm's four-year flirtation with Windows Mobile is over, now it finally has an operating system to call its own again.

Company Chairman and CEO Jon Rubinstein last night said that the Palm would now "dedicate all future development resources to the evolution of webOS" with the result that "going forward our roadmap will include only Palm webOS- based devices".

Palm signed up to use Windows Mobile in September 2005, later releasing the Treo 700W early in 2006.

Back then, Palm no longer owned its own operating system, which had fallen into the hands of Japanese software developer Access, so licensing another one wasn't much of a shock to anyone other than Palm OS die-hards.

Palm later acquired full development rights to the Palm OS, but it soon became apparent that the platform's future was unclear and, in any case, was losing marketshare to Windows Mobile, an OS viewed by many as the only one corporations would consider.

The success of Research in Motion's BlackBerry proved that wrong, but by that stage Palm OS had largely failed to evolve out of the early 2000s. The arrival of the iPhone OS only confirmed the Palm OS' role as a mobile operating system without a future - at least, not without a very radical overhaul.

But that wasn't on Access' roadmap, and Palm eventually decided that it was better off beginning over again and crafting a mobile OS that not only was its own but came without more than a decade's baggage.

Palm has already canned its last Palm OS phone, Centro, in the US, though the device is still available in the UK and elsewhere. It seems unlikely to survive the arrival over here of the Pré. Palm's website still lists the Windows Mobile-based Treo Pro, and it'll be interesting to see how long it stays hanging on in there.

As for Palm itself, at least it is now once again fully in charge of its own destiny, as it was until the - with hindsight - disastrous decision to separate operating system from hardware. Planned as a way to encourage third-party hardware developers to support the platform, simply licensing the OS having brought only a few others, most notably Sony, into the fold.

All it really did was weaken the parent, as most such late-in-the-day attempts to 'do a Microsoft' and turn a vertically integrated hardware and software company into separate entities.

The notion that because selling operating system software worked for Microsoft it can also work for any other technology company is absurd. You need big sales volumes to make it occur successfully, and every technology firm that has followed Wall Street's hints that it should implement just such a transition has done so precisely because it lacked that degree of marketshare.

We wouldn't have seen a resurgent Apple if it too had heeded calls to take the same approach, and we very nearly didn't see the Palm OS-less. Symbian, once just such a platform OS, is now owned by a hardware maker, Nokia.

Windows Mobile never became the Windows 95 or even the Windows 3 of the handset market. Palm's latest move shows it never will. ®