Improvox?... Or something else?Looking for a recording app with all the fixings.And audiobus

So, the most recent discussion on Improvox was from 2013. And while most people seemed to like--even love--it, the general report was that it was still fairly inaccessible. I was wondering if it was worth me purchasing it. I like the idea of being able to sing over music in my library in addition to it's various features (the harmonizing and such.) Or is there an app that works better? I'm a high school student with limited funds so I don't want to buy an app that isn't worth it.
Or would it work better through auto bus? What's you guys's view on that?

Thanks in advance for all responses