The Freegal App is designed to find libraries that have the Freegal Music Service, to store your login information, to search and browse the Freegal Music collection of your library, and to download, store and play your Freegal MP3 files.
Currently, the Freegal Music App cannot export files to Itunes or any other software. Please refer to the FAQ "How do I backup Freegal Music from my iOS mobile device into iTunes?"
As a Freegal Music user, you can download a song again for the purpose of having a copy in your Itunes and in the Freegal Music App. You can do that within 2 weeks of your original download by accessing your library’s Freegal site via a computer, and accessing the “recent downloads” functionality on the navigation bar of the home page (HINT: you may need to log out of the Freegal Application to do this. You log out by going to “settings” within the Freegal App.