This research aimed to identify how well does the current version of the PlanEat app supports the needs of its user base and how it can be improved in a redesign. The PlanEat app is operating on B2B market and is used by nutritionists, doctors and personal trainers for producing customized nutrition plans for their clients. The process of generation of the nutrition plan is based on complex algorithm which considers multiple variables to make the plan as precise as possible and therefore usable also for clinical practice. Unfortunately, the development of the algorithm surpassed the development of the user experience and user interface to that extent that potential users needs to take part in software trainings in order to use the app to its optimal capacity. Therefore, this user-based investigation set to identify users’ needs, interface and functionality issues and use the results as a base for development of a new design of the app’s interface. Since the numbers of people with obesity and consequential illnesses is on rise in Slovakia and other countries the demand for nutrition guidance rises as well. Improvement of the app’s user interface and accommodation of other user’s requirements should result in easier and more effective usage of the app and therefore support production of affordable nutrition plans and education in this area.