Sendo, one of the earliest hardware partners for Microsoft's Smartphone 2002 OS, will instead license the Symbian software, which is backed by several major handset makers. Both Microsoft and Symbian's software is used with cell phones designed for next-generation wireless networks to access e-mail and the Internet.
In addition, Sendo will license Nokia's Series 60 user interface, designed for Symbian.
"Earlier this fall we reviewed our smart-phone strategy," Sendo CEO Hugh Brogan said in a statement. "While our mission of providing customers with feature-rich and ubiquitous devices remains unaltered, seeing that the Series 60 fully embraces both our mission and the new strategy, we decided to approach Nokia."
Nokia's software "utilizes open standards and technologies, such as MMS (Multimedia Message Service) and Java, jointly developed by the industry," he added. "The platform is robust, yet uniquely flexible, bringing great benefits to licensees, operators, developers and consumers."
The announcement comes only a few days after Sendo's formal unveiling of the, based on Smartphone 2002. At the time, Sendo said it planned to put the handset on the market later this year or early next year in partnership with network providers around Europe. The handset was delayed several times while Sendo and Microsoft waited for data-centric networks to become more widespread.
"We have decided not to ship the Z100 because we have terminated our Microsoft agreement. We are no longer a licensee," Sendo spokeswoman Marijke van Hooren said. The Z100 handset was expected to use Microsoft's Smartphone 2002 OS. The company had worked on the device for about two years.
Hooren acknowledged that Sendo had been a few days away from shipping the device to carriers, but wouldn't say why the company decided not to release the Z100. Wireless carriers had approved the smart phone, according to Sendo.
"For legal reasons, I can't say why," Hooren said.
Hooren would not say if Sendo was taking legal action against Microsoft.
Hooren said that Sendo decided to take up with Symbian and Nokia because the company was given access to the OS source code. "Our business model is focused on customizing for operators. We didn't get access to the Microsoft source code," Hooren said.
Vince Mendillo, a Microsoft director of worldwide product marketing for mobile devices, said that Sendo's actions were likely to slow carriers and Microsoft's operating system down, but carriers such as Samsung, HTC and Compal were waiting in the wings.
"We're disappointed that Sendo wasn't able to commercialize their device, and we're working with carriers to find other OEMs (original equipment manufacturers) to step in," Mendillo said.
IDC analyst Tim Mui said that Sendo had arrangements with seven European carriers to use the Z100 device.
"It seems strange that Sendo would not release their device when it was near the end of its development process," Mui said. "There were probably other issues other than just technology."
ZDNet UK's Matthew Broersma reported from London.