How do you design a mobile app that truly changes people's lives? How can you understand how a new service is being used, both quantitatively and qualitatively? How can you use all of the rich sensing and I/O capabilities of mobile devices to create experiences that go far beyond what's possible on a traditional computer? Mobile devices are changing the ways that we interact with each other and information in the world. This course will take you from a domain of interest, through generative research, design, usability, implementation and field evaluation of a novel mobile experience. You'll finish the course with a working, field-tested application suitable for release in the app store as well as a deep understanding of human interaction with mobile devices and services. Based on a popular MIT class that has been taught since 2006 by Frank Bentley of Yahoo Labs and Ed Barrett, a Senior Lecturer at MIT, this course will explore what makes mobile devices unique. A primary focus will be on studying existing behavior and using key findings for design. While writing the code for an app is a part of the class, the majority of the topics will cover designing and evaluating a unique mobile experience. Along the way, you will have opportunities to share your work with other students from around the world! Java experience (or Objective C for iOS users) and a smartphone are required.