Background: Mental health apps (MHA) as a new form of self-help have gained popularity over the last years. Tentative evidence has suggested that MHA might also present a first step into the help-seeking process, because their anonymity circumvents stigma. Using MHA might also increase mental health literacy and reduce stigma through psychoeducation, which could encourage formal help-seeking. To date, it remains unclear how MHA usage relates to stigma, mental health literacy, and utilization of professional help within the public healthcare system. Methods: We conducted a cross-sectional survey with N = 1,263 individuals from the general population (mean age 32.56 ± 11.51, 58.2% female) and employed structural equation modeling to investigate associations between stigma (against individuals with psychological disorders and against help-seeking), mental health literacy, MHA usage, and service utilization within the public healthcare system for mental health problems. Results: MHA usage is high within the general population (40.5% of participants). Results indicate that higher stigma against help-seeking is associated with and increased likelihood of MHA usage, which in turn is positively associated with increased likelihood of service utilization. Symptoms of psychological disorder were associated with higher likelihood of service utilization, but not MHA usage. Conclusions: It can be concluded that MHA appeal especially to individuals with higher stigma against help-seeking and therefore might provide an opportunity to reach underserviced individuals. At the current time, MHA usage appears to take place mostly in a preventative manner or as a supplement to treatment. Better integration into the public healthcare system might help to exploit both preventative and interventional benefits of MHA.