Inclusion Criteria:  Body Mass Index (BMI) between 25 and 50 kg/m^2 English-speaking and writing Own a smartphone with an active data and text messaging plan Own a bathroom scale or willing to purchase a bathroom scale prior to the study start date Willing to be randomized to either group  Exclusion Criteria:  Type I or Type 2 diabetes Currently participating in another nutrition or weight loss program Lost 10 or more pounds (and kept it off) in the last 6 months Currently taking weight loss medications Currently pregnant, pregnant within the past 6 months, or planning to become pregnant in the next 6 months Serious current physical disease (i.e. heart disease, stroke, cancer, or renal disease) for which physician supervision of diet and exercise prescription is needed Physical problems that limit the ability to exercise daily History of clinically diagnosed eating disorder Report a past diagnosis of or current symptoms of alcohol or substance dependence Diagnosis of schizophrenia or bipolar disorder Hospitalization for a psychiatric diagnosis within the last year Currently living with another study participant