Active Self-Tracking and Visualization of Subjective Experience using VAS and Time Spirals on a Smartwatch

In this paper, we describe a smartwatch-based system that enables self-tracking and registration of subjective experience (such as pain) using a VAS-like scale, as well as allowing the acquired data to be visualized directly on the smartwatch. The data visualization is tailor-made for the round smartwatch form factor using an interactive time spiral. Our proof-of-concept prototype implementation is described along with a case study where the application has been used to self-track back pain as the phenomenon of interest. It is found that the smartwatch allows momentary self-registration when the phenomenon occurs and that the spiral structure of the data visualization facilitate identifying recurring patterns in the data.