How to transfer free music download app songs to your actual iPhone songs?

How do you transfer free music download app songs to your actual iPhone songs?

In your itunes software on the computer, go to the tab called:" apps" when your iphone is plugged in and recognized in the itunes library, scroll down to the "File Sharing" section at the bottom, select your app from the left hand side list, once you click once on it, it will show your downloaded files on the right hand side. You can either click save to and go to this directory:
C:\Users\USERNAME\Music\iTunes\iTunes Media\Automatically Add to iTunes\ or I'm pretty sure double clicking it will also add it to the library