Symbian has released the latest version of its smart phone operating system, version 9.3, adding support for new wireless technologies.

The new version features an improved start-up time and quicker responsiveness to applications, the company said - both features needed to push the phones into the mainstream, said the company's vice president of product management and strategy, Jorgen Behrens.

He declined to say how much faster the phones will boot up, however, claiming that start-up times also depend on how quickly other elements can start up, like the user interface and other programs.

The upgrade makes it easier for developers to remove features they might not want to include in lower-price phones by pulling out some of the different components' interdependency.

Another notable addition is native support for WiFi. Symbian phones can offer WiFi today but with limited support; the new OS makes add WiFi easy, said Behrens.

The upgrade also supports UMA, which allows users to make and receive VoIP calls over WiFi, and automatically transfer the call to a cellular network when the phone moves out of WiFi range.

Version 9.3 also supports the latest cellular data technology, HSDPA, as well as push-to-talk services. Symbian has added new tools for developers, including OS awareness for the Eclipse/CDT IDE framework and Nokia Corp.'s Carbide c++ development tools.

Phone makers such as Motorola and Samsung have started offering phones based on the Microsoft OS. Once they start to offer more models then Microsoft will become a bigger threat, Spencer said.