The document provides information about designing a mobile application called The Parisian Flea to help users plan trips to the Paris flea markets. It discusses conducting design research including developing empathy for users and creating mental models. It presents personas, user goals and task flows. It also describes prototyping methods like paper prototyping and includes screenshots of a clickable prototype. Finally, it discusses a usability study conducted on the prototype including heatmaps of user interactions and task completion rates.