Phubbing and Loneliness in the Digital Age: A Daily Diary Study on the Mediating Role of Fear of Missing Out

INTRODUCTION: Smartphone use is ubiquitous, yet its impact on social behavior remains a concern. As the act of snubbing others in social settings by using a mobile phone, phubbing is often linked to feelings of loneliness and fear of missing out. However, the day-to-day temporal interactions between these variables are not well understood. This study investigated the within-person fluctuations and directional relationships among loneliness, FoMO, and phubbing in daily life. METHODS: = 13.38, SD = 0.87) who participated in a 14-day intensive longitudinal assessment period. Data were analyzed using residual dynamic structural equation modeling (RDSEM) to examine the temporal relationships and mediating effects among the variables at the within-person level. RESULTS: Phubbing on a given day predicted a subsequent increase in FoMO the next day; conversely, heightened FoMO also predicted increased phubbing behavior the following day. Loneliness on 1 day predicted an increase in both phubbing and FoMO the following day. Furthermore, the analysis revealed a significant day-to-day mediating effect of FoMO in the relationship between phubbing and loneliness. CONCLUSIONS: These findings reveal the within-person dynamics among loneliness, FoMO, and phubbing in daily life, highlighting loneliness as a driver of next-day phubbing and identifying FoMO as a process linking these experiences, with implications for prevention and intervention strategies to improve adolescent digital well-being.