Great GPS / International Space Station Idea

Can someone build an app that alerts me when ISS is in the sky above me based on my phones GPS location. Blackberry preferably.Mon May 17 23:05:10 via web

Just a great, great idea. I remember being in middle school and there was one summer when for 3 nights in a row, my friends and I would sit on the roof of someone’s house and watch the space shuttle travel across the sky. I haven’t done that since. Why? Mainly because I don’t know when to look up.