Increasing use of smartphones is a notable and worldwide phenomenon, and investigating the potential role this use has on population health is a critical area of research. Prior studies have found psychopathology correlated with frequency of smartphone use. However, this research relied on cross-sectional data and solely utilized subjectively reported smartphone use. These methodological shortcomings should be overcome to understand a truer picture of the association between increased smartphone use and psychopathology. Utilizing an intensive repeated measures study design, we used a smartphone application (app) to monitor daily minutes of smartphone use over the course of one week among 68 college students. Using latent growth curve modeling, we found that lower depression severity predicted increased smartphone use over the week. Additionally, greater use of expressive suppression as an emotion regulation strategy predicted more baseline smartphone use, but less smartphone use during the week. These findings suggest that depression and expressive suppression of emotions accounted for significant variability in objectively measured smartphone use. Depression and emotion regulation are discussed in regard to corresponding patterns of smartphone usage. This paper contributes to knowledge of psychopathological correlates of smartphone use by repeated, objective smartphone use measurement.