Visual markers can be used to define new interaction paradigms for mobile phones. We are using d-touch to prototype and evaluate novel mobile interfaces and applications using standard off-the-shelf devices.

We are particularly interested in how visual markers can be used to relate digital information to real spaces and physical objects. Visual markers can be printed on labels and attached to buildings or items. By pointing camera phones to such a label, people can then access or leave information, in a way that is analogous to pointing and clicking with the mouse on the web. History provides a wide range of examples of information dissemination in physical space: from inscriptions on building facades to public signs, from official plaques to secrete signs left by hobos, from posters to graffiti.

Can the combination of camera-phones and visual markers become an extension of the point and click paradigm to the real world? What are the characteristics of this form of interaction? How is this paradigm extending the range of things that we do with our mobile phones? What kind of information do people want to attach to physical places? These are some of the research questions that we are trying to address through our work. While most current work on mobile interaction through visual markers focuses on information retrieval, our own focus is on how end-users attach digital content to markers.

The research is conducted through the design and prototyping of interactive applications that enable us to observe users in field trials. The main application is uWiki, whose design aims at being flexible enough to support a variety of usage scenarios. Other mobile applications let us probe specific areas.