Symbian's smartphone platform is to be unified and made available under an open-source licence via plans announced today by Nokia, Sony Ericsson, Motorola and Japanese telco NTT Docomo. The move is expected to deliver a broader variety of handsets and encourage developers to bring more Symbian-based applications to market.

The plans will see Symbian OS combined with the three most common user interfaces for Symbian handsets – Nokia's S60, Sony Ericsson's UIQ, and NTT Docomo's MOAP – to create a unified handset platform. It will be controlled by a non-profit organisation, the newly-formed Symbian Foundation, and unlike the current Symbian OS, will be available royalty-free to any handset maker that wishes to use it.

Nokia executive vice president Kai Öistämö said the move will revolutionise the industry the way Symbian did when it was formed 10 years ago.

"This will enable an ecosystem to deliver new exciting devices and new services," he said. As it will be compatible with the current Symbian OS 9, the new software will "provide critical mass like no other mobile platform", he added.

Adam Leach, principal analyst at Ovum, said the move is a positive step that will help to overcome the problem of fragmentation, whereby handsets from different vendors all have different builds, requiring developers to code separate versions of an application for each one.

"It addresses the problem of how you roll out applications across all these different mobile devices. Fragmentation has been stifling development," he said.

The roadmap is for the Symbian Foundation to launch in the first half of 2009, with the first complete new release scheduled for the first half of 2010.

However, the move still has to overcome regulatory hurdles, as Nokia plans to acquire all of the shares in Symbian that it does not yet own as part of the process. If this is given the go ahead, Symbian will become part of Nokia.

This may put Nokia in a position to drive development of Symbian, at least in the near future, but Öistämö said that while Nokia is the biggest contributor, the platform "will not be owned by any one single company".

Leach said he believed the move to open-source Symbian OS is partly a response to open-source rivals such as Google's Android and the Limo Foundation, but also to address the fact that the platform is perceived as too closely bound to Nokia.

"When Symbian started, the intention was to make it an industry standard. This hasn't happened, so they are taking the open-source route to shortcut difficulties in ownership," he said.