The Ubiquitous Interactor (UBI) addresses the problems of design and development that arise around services that need to be accessed from many different devices. In UBI, services present themselves with different user interfaces on different devices. This is done by separation of user-service interaction and presentation. The interaction is kept the same for all devices, and different presentation information is provided for different devices. This way, tailored user interfaces for many different devices can be created without multiplying development and maintenance work. In this paper we describe the design of UBI, the system implementation, and two services implemented for the system: a calendar service and a stockbroker service.