The second biggest change is something I've gotten rid of...namely, the manual-select-a-string mode. I think it's somewhat obsolete, especially with the new algorithm. The settings menu is currently a big blank screen...any suggestions you have for what should be there, please comment (and soon).
The third biggest change, probably the graphics.
The fourth biggest change is that it's responsive to the home button, etc, and it exits properly when pressed. Before I release this version, I'm going to have an auto-shutoff feature that will shut it off in case you forget about it. And I plan on having it shutoff if someone puts the phone to sleep without exiting first.
I also may add the musical staff note system I have setup for the as-of-yet-unreleased sister program, Crooner. Again, any requests, please let me know in the next few days.