UX/UI design for websites and mobile apps. UX design is responsible for how the interface works, and UI design is responsible for how the interface looks. The task of a UX/UI designer is to create comfortable and understandable interfaces for users. A UX designer’s responsibilities are extensive. According to research, about 75% of users of websites and mobile applications show trust in websites and applications based on the appearance of the website. Therefore UI/UX designers solve more than visual problems.