Why did you choose to support Windows Phone instead of Android? With limited resources it seems like a waste of time for such a small percentage of market share.

That being said, I don't think the concept is as bad as others are making it out to be. As a college student, I know TONS of people who sell everything from textbooks to notes (might be a good pivot). Problem is, with the introduction of groups for universities, we have preset groups for stuff like this.

One thing I am worried about is a potential spam to groups that I'm in, which would only make me resent your project.

Good luck!