Ninety-nine adults, ages 18-65, with overweight or obesity, will be randomized in total. All participants will receive an mHealth program (App) for program duration that includes activity tracking with a Fitbit, weight tracking with a smart scale, and an app for diet tracking. At baseline, participants will be randomized to either a a) Fully Automated Kick-Off, or b) Human-Enhanced Kick-Off. "Early responders" will continue with to use App, alone. After 4 weeks, "early non-responders" in both arms will be re-randomized once to one of two augmented interventions with human support: Counseling or Check-In. Assessments will occur at baseline, 1 week, 4 weeks, and 3 months to explore feasibility, acceptability, and preliminary outcomes (weight, self-monitoring adherence, behavioral goal adherence).