Prior work has examined how users judge their smartphone use, typically focusing on either usage duration or intention. How these two factors jointly shape such evaluations remains unclear. We conducted a two-week study with 104 participants, who reviewed their screenshots and provided labels of both usage intention and evaluation of time use. Across 73,000 sessions (6.1M screenshots), the relationship between duration and evaluation was initially linear but then bounded: positive evaluations declined and negative ones rose with longer phone use duration but both eventually stabilized, most often judged neutral. Trajectories varied by intention. Entertainment mirrored the overall trend; functional use continually lost positive evaluations, whereas information-seeking became increasingly positive during the first half hour before later declining; messaging-based connections slowly lost positive evaluations, while social media–based connections declined more quickly; finally, “no specific intention” unfolded in phases—from short positive use to regret-prone mid-length episodes to neutral long sessions.

Parents, educators, and policymakers have expressed concern about the future implications of young people's sharing practices on social media sites. However, little is known about how young people themselves feel about their online behaviors being preserved and resurfaced later in adulthood. We conducted semi-structured interviews with 28 college-going, primarily female, young adults about their use of social media and their transition from adolescence into young adulthood. We find that participants recognize archival value in their own Facebook histories, despite sometimes perceiving these histories to be embarrassing. They experience tensions between meeting their current self-presentational goals and maintaining the authenticity of historical content. To reconcile these tensions, they engage in retrospective impression management practices, such as curating past content. They also engage in 'backstalking' behaviors, in which they view and engage with other users' Facebook histories' openly with close ties and discreetly with weak ties. We consider this ludic engagement through the lens of emerging adulthood and discuss the theoretical implications of our findings, especially in light of emerging applications which intentionally resurface digital traces.