“Diabetes Monitor App” is a great contribution to the modern era of development of Human-Computer Interaction. This is a long-awaited need for the people especially elderly diabetic patients. This app is designed in such a way that people of all ages and physically handicap people can use the app. This app is also intuitive and usable. Need findings, observations, interview and survey are performed using the sample involving participants in all relevant aspects. A mockup survey is performed to take the feedback of the participants into account. The outcomes of the mockup survey are used to develop the design of the app. The samples are chosen by maintaining a few conditions. Multimodal design and the universality properties are also addressed to make the design a successful one. Rapid prototyping (paper-based) is preferred for the mockup survey. After that, mobile interface prototyping, video prototyping is used for the final survey. The design has been gradually changed and updated depending on the feedback from the users. Post evaluation of the app has been done. All the testing and evaluation results of the performance analysis have also been incorporated in this manuscript.