I’m not sure when it was added since I hardly play any of the versions I own (I have the Korean, Japanese, and English apps installed on my iPod touch 4G) but here it is on Tap Sonic Korea:

Here’s the play area. ^^

Hmmm … looking around the app’s folders to see where the song files are kept. I found them but all the music is encrypted … even the ones that you purchase with a Premium Pass. 😦 😦 😦