Among treatments for children with ASD, assistive robots are growing popular as they are able to elicit different social behaviors. At the same time, technology is providing methods to automatically collect quantitative data, in order to assist the therapist evaluating the children progress. In this study we introduce a system composed of multiple spherical devices, as well as the design of a turn taking activity using those devices. In previous studies turn taking was found to be an important social skill for development and engaging in activities with others. To evaluate the system performance, a single case experiment with a boy with ASD and the developed device was done. During the activity, the device had two different roles: to engage the child on the turn taking activity and to provide information to the therapist that describe the child's behavior. We could successfully collect quantitative data that represent turn taking as well as we could observe how does the boy manipulate and interact with the device. Based on the results, we are motivated to keep exploring the potential application of devices mediated activities for children with ASD.