Abstract: To address the issue in multi-touch tabletop that the WIMP paradigm-based graphical user interfaces could not handle multi-finger gesture recognition and UI component reorientation,this paper proposes a new multi-touch tabletop UI toolkit,termed MTBuilder,based on the universal foundational metaphors OCGM(objects,containers,gestures,and manipulations).First MTBuilder employs a hierarchical data representation model to store the multi-finger information.Then it configures the gesture recognizers dynamically to improve the efficiency of recognition.Finally design the components of the user interface based on OCGM.Several typical prototypes are developed,such as multi-user InfoScan and city planning.The prototypes and the experimental results showed that MTBuilder can efficiently support construction and prototyping of a tabletop user interface.