A Crap for That

The return statement after a friend or associate tells you that they have an application for a smart-phone that applies to the situation (e.g. finding the positions of the stars) and you profess to them in a sarcastic manner that you do not care.
It is used similar to the phrase "I don't give a crap", however you use a sarcastic tone to convey your apathy

Guy1: Hey, man, check it out! My iPhone has an app that lets me know what the stars look like above us right now!
Guy2: Hey you know, I have a crap for that...