Less than a month after Microsoft launched its Smartphone software, one of its major partners has withdrawn from the programme and defected to the open source community.
UK-based mobile phone manufacturer Sendo has announced that it has licensed Nokia's Series 60 Platform, which sits on top of the Symbian operating system.
Sendo had been developing the Z100 Stinger smartphone with Microsoft, and has missed several launch deadlines. All work on the device has now been abandoned.
"The Z100 will not now be coming to market," said Ron Schaeffer, head of product strategy and planning at Sendo.
"The main attraction of the Nokia product was being able to secure a source code licence so that we can customise the product to suit others."
The announcement leaves Microsoft with only one major mobile phone manufacturer, Samsung, developing for the Smartphone platform.
However, Samsung has been hedging its bets by developing an open source smartphone with Symbian.
"This is incredible news," said Jessica Figueras, a senior analyst at Ovum. "In this market the big device vendors have seen what happened to the PC industry and have organised to stop the same thing happening again.
"Firms like Nokia and Sony-Ericsson are ambitious and want to be more than box shifters for Microsoft."
The move by Sendo is a major win for the open source movement, which has been floundering under sustained pressure from Microsoft.
Although the mobile industry manufacturers and networks have been working closely on open standards, Microsoft is seen as a potentially dangerous competitor.
"We're extremely pleased to welcome Sendo," said Niklas Savander, vice president at Nokia Mobile Software.
"Manufacturers like Sendo have looked into the eyes of operators and have recognised that they want flexibility and customisation. We've now got over 60 per cent of the mobile manufacturers behind us, and that tells you a lot."
Microsoft is a part owner of Sendo, which was set up in 1999 by ex-Philips engineers.
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