Microsoft expects to be joined by at least four handset makers when it launches its new Windows Phone 8 operating system later this year.
Nokia, Samsung, HTC and Huawei are planning phones to be ready for the launch, Microsoft said as it previewed the new operating system to developers in San Francisco on Wednesday. The four phones will be based on Qualcomm processors.
No other details of the phones were announced at the event, which was targeted at software developers.
Microsoft plans to make Windows Phone 8 available in 50 languages and open the application store to customers in 180 countries.
Software updates will be offered direct to the device so users won't be required to connect their phone to a PC to perform an upgrade. Customers will have access to software upgrades for at least 18 months from the launch date of the device they purchase, Microsoft said.
Windows Phone 8 will share the same code base as the desktop Windows 8 operating system -- a big step toward bringing the smartphone and desktop together, but one that means users of existing Windows Phone 7 handsets won't be able to upgrade to the new software.
Instead, those users will get an upgrade from the current version, 7.5, to one called version 7.8. While lacking many of the most important structural improvements, the version 7.8 software will introduce one of the biggest cosmetic changes to Windows Phone: a more detailed home screen with user-programmable tiles.
Microsoft didn't say when the version 7.8 update would be available.
Existing users of Nokia Lumia handsets will also get a number of software updates "in the coming weeks," said Kevin Shields, who leads Nokia's Lumia development.
The updates will include the ability to stream media to DLNA (digital living room network alliance)-compliant consumer electronics devices, an updated music app, a counter app that offers updates on voice, data and messaging usage, new camera software and updates to Nokia's maps, transit and driving navigator software.
Martyn Williams covers mobile telecoms, Silicon Valley and general technology breaking news for The IDG News Service. Follow Martyn on Twitter at @@martyn_williams. Martyn's e-mail address is email@example.com