I saw a demo of an iPad app called Scorecerer... sells for $10.

It was the first program I saw that would receive MIDI data to select the song. And during the playing of a MIDI file, you can insert page changes.

Here's the website... http://www.deskew.com/

Here's a demo of it being used with Ableton Live...
http://www.youtube.com/watch?feature=player_embedded&v=Q9ATpiqXt6c


I wonder if setting the registrations within a song on the Tyros is doing the same thing as this guy did in Ableton Live?!?