Two things.

1. Don't worry about the idea. They tend to change a lot. Pick something that interests you, roll along with it, and if you don't like just move on to a different idea.

2. I'm a college student too. One thing that hasn't been mentioned yet is IP and the University. Talk to your professor about this carefully to make sure that your IP is yours and the University doesn't get any claim, just to alleviate headaches from happening later. In some schools, if you use the college's money or resources to create something they legally can claim a piece of it. Make sure you know about these details before embarking on any business venture.