Longitudinal mental health data collected via the Corona Health smartphone app during COVID-19.

Mental health impacts during the COVID-19 pandemic underscored the importance of real-time assessment methods to capture population-level changes (e.g., longitudinal changes in quality of life). This dataset contains questionnaire responses collected with the Corona Health app, a multilingual mHealth app available on Android and iOS platforms. The dataset includes baseline from 2,704 participants (i.e., adults aged 18 years and older, living in Germany) and 11,541 repeated ecological momentary assessment (EMA) responses, providing longitudinal mental health data throughout various phases during the pandemic period (i.e., data collected between July, 2020 and January, 2025). The questionnaires assessed domains such as quality of life, psychological well-being, coping mechanisms, and pandemic-related concerns. In addition to questionnaire responses, the dataset includes sensor data such as GPS location information and app usage statistics collected with participant consent. The described dataset enables researchers to examine mental health trajectories during and after COVID-19, analyze relationships between psychological factors and pandemic experiences, and investigate patterns in longitudinal mental health data.