Patient progress tracking is important to a doctor in a treatment process. In order to have enough information about a patient and the treatment made for the patient, a doctor has to view a lot of medical data about symptoms, test results, drugs and their dosages in a period of time. With electronic medical records, it is convenient for the doctor to view and search for any information he/she needs as compared to paper medical records. It would be even better if all the related electronic medical records over time of each patient are visualized appropriately to support the doctor in patient progress tracking. Therefore, our EMRVisualization system is proposed as a web-based application on tablet computers for visualizing all the related medical data in an integrative manner. The system provides an interactive visualization with accurate data at different detail levels, quick access and convenience for a doctor to keep track of the progress of each patient over time. Its demonstration with the real data of gastroenterological Vietnamese patients in Thong Nhat Hospital, Ho Chi Minh City, Vietnam, has been conducted and showed that every interaction of a doctor can be accomplished in at most two steps.