Developing while in College

I will be entering my freshman year of college this fall. As you know college is expensive and many are forced to go to school and work. I've got some programming experience through AP CS, and almost half way though Stanford's iOS course CS193P.

My question is can I develop applications in college and have it replace a part-time job? Is that realistic? I hope to have my first app up on the App Store before I graduate HS in June.