Multi-device application development takes into account several characteristics and constraints of each device. Interface specification languages and architectural models have been used by user interface designers. Within this context, this paper presents the user interface specification language UIML (UIML2 - User Interface Markup Language 2.0) and the architectural model MIM (Meta-Interface Model) that have important role in user interface design for multiple devices. Furthermore, this paper discusses the development of a user interface software generation tool from UIML specification