If you are looking for how to play freely in Pianist HD: Piano+, here are 2 simple steps to do it. Check it out!

Step 1:

Look at the top menu bar, tap and hold the “Playback” icon on your right side.

Step 2:

You did it! Now you can play freely whatever song you like. You can turn on the "Freeplay Mode" either on the main screen OR while playing a particular song which you don't want to continue anymore.

Noted: How about change into another song? Simply tap "Songbooks" my dear.