The iPhone’s impact on the mobile phone world is still being felt, as the mobile phone’s user interface becomes the star attraction (and not before time!). The latest news comes from Motorola, who’ve just bought a 50% stake in user interface company UI Holdings BV, the parent company of UIQ Technology AB.

For those not in the know, UIQ technology make mobile phone user interface software, and were wholly owned by Sony Ericsson after being spun off from Symbian. The UIQ user interface can currently be found in the Sony Ericsson P1, W960 Walkman and Motorola Z8.

Tthe announcement by Motorola reflects well on Sony Ericsson’s commitment to keep UIQ open in an attempt to make it a strong, independent cross-vendor user interface for smartphones and media-centric phones.

According to the press release, both Sony Ericsson and Motorola are now committed to expanding the shareholder base of UI Holdings to include other handset vendors. Their aim is for UIQ to be an open standard across multiple mobile phones, and to get as many people developing its features as possible – which they’ll need, if they’re to compete with the glorious iPhone’s user interface.