O2 has announced that it is calling for customers to enrol as members on its new developer platform, O2 Litmus.

Since its launch in December, O2 says Litmus has already seen a "wide range" (150) of wireless and internet-enabled applications and services for O2 customers to be able to test and approve.

O2 Litmus customers will receive free access to any application they test once it becomes commercially available.

Then, O2 Litmus users will be asked to rate their overall experience of each application for "tangible rewards" in return.

Through a partnership with Mob4Hire, users will be able to "bid" for each application they wish to trial, putting a value on what they think their time is worth.

"Opening an apps store has become the new mobile vogue. But for O2 it misses something fundamental: the collaboration of customer, developer and the network operator", says James Parton, head of O2 Litmus.

"We are in the unique position to be able to draw on over 19 million customers and offer those with a proven interest in new mobile technologies and a real thirst for new ideas the chance to shape the future of their network by working directly with software developers to provide feedback on mobile applications that have been designed for them".

O2 Litmus apps are available on the Motorola V3, Nokia N95, O2 Xda Orbit II, Samsung U600 and the Sony Ericsson W910.