The mobile OS made by Linux house Ubuntu received a significant boost this week as China Unicom signed up to the Ubuntu Carrier Advisory Group and potentially add its 300 million subscribers to the user pool.

Ubuntu parent and open source software developer Canonical established the Carrier Advisory Group for its Ubuntu smartphone OS last month. The group is led by David Wood, a former Psion engineer and one of the founder members of the original Symbian collaboration.

A number of large operators, including LG UPlus, SK Telecom and Korea Telecom from Asia Pacific and Deutsche Telekom, EE, Telecom Italia and Portugal Telecom from Europe have already signed up.

Canonical said that the CAG will hold regular meetings in a bid to steer the development of the Ubuntu mobile platform. Key discussion topics will include strategies for differentiation, application portability from Android and Blackberry environments, revenue share models for publishers operators and device vendors and market positioning.

Li Xingxin at China Unicom’s terminal research and support centre said; “Ubuntu can be an exciting new platform for the Chinese market, offering a brand new user experience that balances user simplicity with operator requirements”.

The smartphone version of the OS, Ubuntu Touch, may be ready for release in the late summer or autumn.