Background: Monitoring patients and achieving adherence in chronic diseases is an important problem. Allergic rhinitis (AR) happens to be one of the most common chronic and lifelong conditions of today. As such, it proves to be an excellent model for identifying the determinants of app use in the monitoring of adherence to treatment and assessment of health status during treatment. The use of Mask-air® app supports clinical decision-making by actively involving the patient in the process of observing symptoms and by promoting adherence to therapy. The main objective of the study was to identify the defining characteristics of a Mask-air® user, describe their disease phenotype, satisfaction with app use, as well as potential reasons for abandoning it. Material and Methods: The study included adult patients receiving care in an allergy outpatient clinic. In the course of a routine visit they were offered to participate in a trial involving the Mask-air® app. By means of surveys/questionnaires investigators collected data regarding their symptoms, administered treatment and clinical evaluation results. At a follow-up visit, these were compared, and patients was queried about their satisfaction with app use. Additionally, patients presented and discussed their app records. Those who refused to install or utilize the app were asked to indicate their reasons in a questionnaire. Results: The study found no distinguishing characteristics of Mask-air® app users, compared to those who refused the app. Readiness to use software was analyzed according to age, economic status, disease advancement and severity, presence of allergic comorbidities and therapeutic modality used. Respondents fell into the following categories in the context of app use: those who did not install the app (11.6%), those who installed it, but did not use it (22.2%), and those who installed and evaluated it (66.2%), but did not produce symptom monitoring records (15.6%). Satisfaction ratings for app use were high, but patients were critical of the therapeutic aspect included in the app. Conclusions: No distinguishing features of the Mask -air ® user were identified, suggesting that the Mask -air ® app can be recommended to all patients regardless of gender, economic and educational status, or disease phenotype.