Blind people can access visual information through tactile graphics. But, tactile graphics have some problems so that blind people need rich experience to understand tactile graphics. Therefore, systems that arc implemented audio guidance capabilities to tactile graphics have been studied. However, because of the limitations of the current audio-tactile graphic systems, few of blind people use the audio-tactile graphic systems. Some of the reasons are as follows: (1) the systems need special devices which are often expensive; (2) the systems require users to produce specific tactile graphics to the systems because existing tactile graphics are not available to the current systems; (3) since the special devices are large, this degrades the portability of the systems. Focusing on the above three problems, we are developing an audio-tactile graphic system executable on smartphones. In this paper, we show our current prototype system and discuss how effective audio guidance to understanding tactile graphics.
