The use of digital technology in the form of health care apps has been on the increase. In the nutrition area, apps are now available with a view to lead to behavior change, helping individuals to reflect on their food choices and identify weak points in their dietary routine. The article seeks to evaluate user perception regarding the usability of the Digital Food Guide (DFG), which is a mobile smartphone app with guidelines on healthy eating. A cross-sectional study evaluated the user perception of the app using the Likert scale, built with 24 assertions organized in three dimensions of analysis: the DFG as an intuitive and self-explanatory tool; the DFG as a promoter of healthy food choices; and the DFG as a promoter of the transition to the appropriate weight. The instrument was assessed regarding its reliability through the split-half and validity method in two stages. The 22 assertions were validated; the reliability was 0.93; the average of the assertions in each dimension was 3.10; of the 80 respondents, 58.75% considered the implementation of the DFG to be positive. The application has good usability as perceived by users, considering analysis of the dimensions relating to its performance.