Clarification: Your priority should be designing a compelling interaction that meets the needs of your user in your identified usage scenario. Concentrate on each and every user interface element---if we were to point at any aspect of your interface, you should be able to give a reason as to why it is there. That reasoning should be founded on your user's needs, not on any engineering or technical considerations. Implementing a backend or more involved technical components should be done only to the extent that it enables you to create a prototype that produces the best possible user experience.
You will take your interactive prototype and bring it a level where your user can independently operate it. The goal is not to focus on the polish of the system, but to give your user the flexibility to accomplish the problem you are addressing.
Extend your interactive prototype to add functionality to your interface that allows your user to perform the general task of your problem statement, not just the specific tasks of your paper and interactive prototypes.
Concentrate on designing for a specific user. This means designing for example, "a bicycle courier in San Francisco," not "people who work in offices."
Focus on making the prototype functional while still taking interaction design decisions into account. The objective is to build a system that allows users to accomplish the problem you are trying to address and get a good idea of how the final product would function. This may involve implementing live sensors, a database or web service, or a high-tech Wizard of Oz system. Your prototype should now run on a mobile device.
As stated in the FAQ, the purpose of implementing functionality is to learn about how to better design the interaction, not to do busy/engineering work. By making your project more realistic, you will uncover design issues that may not be apparent with Wizard of Oz alone. Your final project will be evaluated on the design of the interactions, and you are certain to produce a better interaction if it is more realistic.
The functional prototype need not be completely polished. This is not a graphic design class. Provided your interface is clean and well-organized, the aesthetic design is unimportant. You do not need have to have fancy animations or amazing 3D icons (unless you have user need-based justification).
You should expect to complete all desired functionality of your prototype for this assignment. You will be using this prototype for user testing before final presentations. The intention is to make it easier uncover unanticipated design issues in the user testing assignment.
After the user testing, you will be revising this prototype based on your test results for the final presentation. For more information on the scope of the final project, see the final project page.
The assignment was graded out of 100 points. The points were broken down as follows: