User Experience (UX) Development is the procedure of improving the overall experience of the users when they interact with the application or website in order to achieve its objective to... provide the maximum customer satisfaction. It keeps customers in mind and creates the basic skeleton of any application. It mainly focuses on wireframing an application and structuring all its components and elements appropriately to create the user flow.
The User Interface (UI), on the other hand, is the process of improving the presentation and the interactivity of the web or mobile application. It focuses on the app’s look and interacts with... the users. Each screen, page, buttons and other visual elements you see while using an application is the User Interface of that application.