It has been over a year since we conducted the first of two planned studies in POSTCOVID-AI. After several intense months of data exploration in the initial study, along with the incorporation of certain technical improvements in the app and data collection system, we are now prepared to commence the second study of POSTCOVID-AI, scheduled to begin in the upcoming weeks. This new study poses an even greater challenge than the previous one. While the goal remains to collect the same type of data over a similar time frame (approximately one month), this time around, we are working with a significantly larger participant group. In fact, the objective is to replicate the first study with a sample of approximately 400 people, quadrupling the number of participants from the previous study, thus representing one of the largest mobile longitudinal datasets to date. This increase primarily aims to provide stronger support for the knowledge gained from the initial study up to this point and to yield additional data for the formulation of new hypotheses.