This is a very collaborative process. As the UX is working out the flow of the app, how all of the buttons navigate you through your tasks, and how the interface efficiently serves up the information user’s need, the UI is working on how all of these interface elements will appear on screen.

Design Strategy is the intersection between business profitability and value for people. ... In other words, it ensures your team produces what your business needs to align its success to its customers' needs. Design strategy is the term used to describe the nexus between corporate strategy and design thinking.

Product design is the process designers use to blend user needs with business goals to help brands make consistently successful products. Product designers work to optimize the user experience in the solutions they make for their users—and help their brands by making products sustainable for longer-term business needs.