Using a daily monitoring framework, we examined the psychological consequences of Fitbit self-tracking on state body satisfaction, disordered eating (DE; i.e., binge eating and dietary restraint), levels of exercise engagement, and motivations (appearance vs. fitness/health) in adult women. A further aim within the Fitbit group was to assess whether the level of steps achieved on 1 day would be associated with the state-based outcome measures on the subsequent day.