This workpackage will research interoperability in the context of mobile devices, which are the most widely-used access device for information society services and provide ubiquitous access to applications and services. Taking into account the results of the user tests in WP 1 and the technology state of the art from WP 2, this workpackage will research into interoperability of mobile devices with their environment to enable such devices to communicate using different communications protocols on the market and conceive a multimodal interface adapted to different disability types and allow interaction with different mobile elements. In the same way, it will investigate integration of content with mobile devices in such a way as to make it accessible and that access can be configurable as a function of the device and the special abilities of the user.