Mobile Linux body, the LiMo Foundation has signed up some new members as competition among new mobile Linux platforms heats up.

Trolltech, Acrodea, ETRI, Huawei and Purple Labs have joined the group which, along with founders NTT DoCoMo, Vodafone and Motorola, now consists of 25 members.

Trolltech said that it quit its participation in the Linux Phone Standards Forum (LiPS Forum), a group setting mobile Linux standards, in favour of working with LiMo. "This is a solution based on code, not just a specification," said Benoit Schillings, CTO of Trolltech. Trolltech decided that LiMo's efforts were more likely to produce a real product before the LiPS initiative, he said.

Trolltech's conversion comes after the LiPS Forum chose to base its user interface framework on Gnome's GTK toolkit, rather than Trolltech's competitive application platform and user interface for Linux phones.

Trolltech's change of heart is indicative of the heated competition in the fledgling market for Linux mobile phones. In addition to LiPS and LiMo with their different goals, Google has announced its Linux-based Android.

While Android and its Open Handset Alliance supporters are creating a competitive offering to LiMo's software, LiMo's head says its effort has advantages.

"An important difference is that the code within the LiMo platform is market-proven technology that has been brought to the platform by our founder members in the form of Motorola, Samsung, NEC and Panasonic," said Morgan Gillis, executive director of LiMo. "We simply reintegrated it to form the first release of the LiMo platform." That contrasts with Android, a new software platform containing "unproven code" that Google has only just produced, he said. It typically takes two to three years before handset software is stabilised and ready for volume production, he said.

LiMo expects to unveil the first release of its open Linux-based operating system as well as APIs for developers during the first quarter. It also expects that the first handsets based on the software will hit the market during the quarter.