How do you delete songs?

Super awesome app! Love looping, cutting, and mashing. But please, how do you delete these songs? I already made the wave files and listen to those on my iPhone. I dont need the mash files within the app anymore, right?

If anyone can tell me, or better yet, post it! Ill make 5 stars.

Astral Shade about iMashup, v4.0.1