Despite theoretical arguments that brief app-based interventions could be a useful adjunct to longer traditional treatment programs, there has been limited evaluation of the acceptability, feasibility, and efficacy of these micro-interventions. In the present study, 247 women from the general population were randomly assigned to the intervention or wait-list control condition, and provided measurement of body satisfaction and related constructs (body image importance, confidence dealing with body image issues, eating pathology, and self-esteem) at baseline and 21-days (post-intervention). During the 21-day period, the treatment group received access to an eHealth platform containing a series of brief video activities (e.g., gratitude tasks, breathing, and relaxation) previously demonstrated in experimental studies to improve body satisfaction. Findings showed greater improvements in body satisfaction at post-intervention for the intervention group than the waitlist controls (Cohen's d = .42). Use of the intervention content was associated with immediate increases in state-like body satisfaction ratings, and the magnitude of these in-the-moment improvements was predictive of greater post-intervention symptom improvement and retention (ps < .05). However, the intervention did not produce change in constructs related to body satisfaction (Cohen's d ranged from 0.02 to 0.13). Overall, findings offer support for micro-interventions as a spot treatment for specific symptoms, and possible means to maintain engagement and motivation within a broader treatment program.