App-based Stress Management with the MHealth Application "harmony"

The purpose of this study is to investigate the efficacy of app-based stress prevention via the harmony application in a prospective, interventive, monocentric, explanatory pilot randomized controlled trial (RCT), with participants\' subjective stress experience as the primary endpoint. Research question: Does usage of the app harmony have a positive impact on the subjective experience of stress of its users? Do usage frequency, intensity or width of content engagement influence the efficacy of the intervention? Hypothesis: We expect improvement of participants\' subjective stress experience, stress-related symptoms, subjective well-being, resilient coping, self-efficacy, life satisfaction and goal-attainment.