The idea of your assignment is to take what you have learned in the classroom and apply it to an interface, any interface. The lovely thing about an assignment like this is that there is no wrong answer, as long as you objectively apply the principles you have learned. Pick any
application. I can tell you 15 or 20 different applications that I think have poor interfaces, and you may not agree. You may find an application that you hate, and I may think is fine.
You were perfectly clear. I have taken Human factors, and I have done the same assignment that you are doing. What I am trying to prevent is someone coming along that has no clue what you are trying to accomplish, and biasing your opinion. We are also concerned that some malicious person may post a link to an 'application' that is actually malware, and infect some of our members.
This is a gravy assignment as long as you can put together a well thought out argument. The actual application that you choose is irrelevant. I am assuming that your assignment also allows one to critique websites also; if that is the case, any random website will do.