Subjective sleep quality monitoring with the hypnos digital sleep diary: Evaluation of usability and user experience

Sleep diaries are records of individual's sleep and wake times, extending over a period of several days up to several weeks. Sleep diaries are often used to support the diagnosis and treatment of sleep disorders though the emergence of self-tracking technologies also makes them interesting for intrinsically motivated individuals who wish to gain insight into their sleep patterns and related influences. This paper introduces Hypnos, a digital sleep diary, and a user study aimed to its usability and the resulting user experience. The study involved eighteen participants without a diagnosed sleep disorder for a period of ten days. Overall Hypnos was found useful and usable which supports its application in practice, but it is advisable to make the user experience more attractive, stimulating and innovative in order to also make the self-tracking more intrinsically motivating.