Abstract
A wide array of consumer devices that purport to measure sleep are now available, with sleep measurement often an additional feature alongside the measurement of daily activity through steps and monitoring of heart rate. These devices offer their users insight into the duration of sleep and different sleep phases and the ability to share the outcomes in the form of numbers, charts, and graphs. This paper explores the ways in which these technologies are deployed within everyday online interactions. We explore depictions of sleep self-tracking that are commonly available online and analyse how the sleep data collected are interpreted by users and deployed in differing social interactions through a comparison of traces of the Fitbit sleep self-tracker across Twitter, Instagram, and the parenting discussion forum Mumsnet. We find
that sleep self-tracking is, across platforms, occasioning new practices of evidencing sleep that acquire particular meaning within existing relationships. There is also however a strong mood of rejection, mistrust, and doubt around self-tracked sleep. The new ways of evidencing sleep sit alongside and in dialogue with previous ways of knowing sleep and of deploying it within social interactions, rather than displacing them.