mic problems

hi i am new audacity i tried to record my song in i used the microphone on my ipad but when i hook the 3.5 jack in and selected mic it does record anything but when i pick headphone its records please help

The connection on an iPad is not a simple Mic-In or Line-In. I believe it’s designed for complex headsets like for Skype or other communications.

We went through this once with a friend in New York. We found two ways to do it. This is a simple adapter cable that goes between a Computer Microphone like the Logitech Desktop Microphone and the iPad.
http://www.kvconnection.com/product-p/km-iphone-mic.htm

The other company is much better at it, but much more expensive.

iRig and Amplitube.

I know nothing about any of these products.

Koz