User interface design (UI), by definition, is the design of user interfaces for software such as mobile apps, with a focus on maximizing user experience by employing design principles that concentrate on usability and utility. Good user interface design ensures that interface elements are functional, easy to access, and easy to understand.

User experience (UX) refers to user emotions and attitudes regarding the use of a particular product, in our case, mobile applications. User interface design and user experience are interrelated since the quality of an individual’s experience using the application correlates with the quality of interface elements.