In recent years, we witnessed the spreading of a plethora of wearable and mobile technologies allowing for a continuous and "transparent" gathering of personal data. People are increasingly visualizing information about physical activity, health, everyday movements, and mood to monitor their routines, increase their performance, or change their behavior.Two decades ago, lifelogging research, which originated in research labs, attempted to make everyday recording effortless [1,2], aiming at creating a sort of "total" repository of an individual's life. In more recent years, however, the idea of endlessly hoarding personal information for archiving purposes made way for the ambition of using such information to increase users' self-awareness, highlighting the need to make data useful for their situated purposes. The so-called Quantified Self (QS) movement first foresaw a future when individuals could manage their own data to raise their self-knowledge. Quantified selfers enact practices of self-experimentation in which data are used to understanding the factors that may influence a (problematic) behavior or condition (e.g., a chronic diseases) [3].In this vein, personal informatics (PI) research attempted to explore novel forms for collecting and displaying personal information. PI researchers aimed to go beyond the quantified selfers' specialized practices, supporting the "use" of personal data in individuals' daily living. There are a variety of domains, such as health, sports, fitness, and transportation, that might benefit from the increased availability of personal information. By making such data actionable, PI research aims at supporting people in understanding the richness of their own digital traces, thus increasing the meaningfulness and value of data.However, a variety of challenges still need to be addressed in order to achieve such a goal. For example, despite the recent advancements in automation for recognizing and mining emotional, cognitive, and behavioral information, an active role of the user through self-reporting is still required. Data "curation" is burdensome demanding efforts and time to be accomplished. This task cannot be easily managed without strong motivation and compliance over time, so that many users fail to report their data, making the use of self-tracking tools quite useless [4]. It is paramount, therefore, to find new ways for engaging users in actively collecting their data, making this activity more enjoyable and sustainable in their daily living [5].Moreover, numbers, per se, are not meaningful, and data need to be "narrated" [6] and integrated in the users' personal histories and system of meanings in order to really develop their self-knowledge [7]. Although PI research strived for designing visualizations going beyond stats and analytical representations, for example by using natural language [8], glanceable displays [9], metaphoric depictions [10], and multiple visual cuts [11], there is room for the exploration of radically novel modalities for managing and feeding info...