Unfortunately Fun Folds is no longer available on the store, but I interviewed the creator in 2012 at WWDC. Of course, considering it was based on a bit of pop culture, do we expect those apps to last anyway? Occasionally I'll download the random meme app of the week, but in the end most of these are "throwaway" apps.
That said, Fun Folds had good interaction design and could have easily been re-purposed. If it has, I'll follow up with a post about what happened to it. Until then, hear about why the developers created Fun Folds to begin with on this episode of Origin Stories.