User Experience (UX) is creating a seamless experience for the user. UX is the process that the user interacts with the product. As the UX design for an application, you need to think like the user.
User Interface (UI) is how your content, assets, icons are designed and what the user is interacting with first to last. Visual elements on where to put the buttons and icons.
Go through an in-depth process of questions and history about the project. Creating rough concepts to get an understanding of what clients want. In Adobe Illustrator go into detail about a few design ideas. Rinse and repeat until everyone is satisfied.
