The development of digital technologies transforms the design targets, characteristics of the targets and the role of designers. The paper highlights the role of prototyping in the interactive digital product design process and presents the survey and analysis of prototyping tools that can be used by designers in designing such products. From the review of tools in design related fields. the classification framework for the tools were presented. The framework has the criteria of the fidelity of prototypes, the stage when the prototyping is used, and design targets. Based on the analysis, the implications for using the tools are suggested. They includes that prototyping is important in the concept stage for designers and different tools and methods are to be applied according to design targets and objectives. Prototyping tools need to support exploring design concepts without being constrained by implementation technologies The collaboration with other professionals can also help effective prototyping. Existing tools familiar to designers can be effective platforms for the new design problems. The results can be guidlines with which designers choose more appropriate prototyping tools when they face new design problems. It also make practical contribution in improving design efficiency and design education for interactive product design projects.