Background: Type 2 diabetes mellitus (T2DM) affects 12.8% of the population in Costa Rica. Mobile technology has increased in Costa Rica and it allows an innovation in the mobile application field T2DM care. Objective: This study aimed to explore participants’ perspectives related to the design of a mobile application to support T2DM care in Costa Rica. Methods: A qualitative design was used to explore participants’ perspectives. Focus groups and semi-structured interviews were conducted with 16 T2DM patients, and semi structured interviews were held with 12 healthcare professionals (nutritionists, nurses and medical doctors). Results: Only two patients had ever used an app for T2DM care, and only two professionals had previously recommended the use of these mobile applications. Both groups were willing to use these mobile applications. The most common function for which both groups showed interest was the record of blood glucose, but other functions were also mentioned. Healthcare professionals recommended continuous professional supervision in the use of these mobile application. Conclusions: Potential mobile application users provide valuable insight regarding their needs and expectations for a T2DM care mobile application. Simplicity and being culturally adapted to Costa Rica are the most desirable mobile application features mentioned by the sample.