As the need for health care services increases, some health facilities in many developing countries such as Namibia are challenged with accessing its big data. Despite the success of mobile systems, its use to access health care big data is challenging, which have impact on manageability and improvement of service delivery. The main problem is that the factors that influence interaction between mobile systems and health care big data are not empirically known within the Namibian context. The Namibian Ministry of Health (MoH) was therefore used as a case in this study. Qualitative methods and an interpretivist approach were employed, and structuration theory was used to underpin the study, which means the theory guided the analysis of the data. From the analysis, five factors were found to influence interaction in the use of mobile systems to access health care big data. On the basis of these factors, a model is proposed, which is a contribution to improving health care service delivery in the country through its practical implications: guiding interactions among health care stakeholders and developing policy for accessing patients' big data.