There is a lack of synthesized evidence focusing on the design and development of mobile applications targeting the care of patients with breast cancer. This gap will impede understanding of care through mobile applications and hinder digital health intervention strategies that support these patients. Considering the increasing needs of breast cancer patients, the magnitude of care burden, and the widespread use of mobile applications, increased studies are needed to improve care in this population. For this purpose, the mobile application to be developed in the project will include information that patients will need in the perioperative period, preoperative training, exercises to be done in the postoperative period, symptom management, nutrition and lifestyle content. Thus, it is thought that the mobile application will contribute to consultancy and care on issues such as patients' quality of life and symptom management.