This is a pretty good app for what I paid. (nothing) at first I was fairly excited about VirtuosoPianoFree3, I downloaded it and opened it up fore the first time, and saw the basic middle-c octave, and played a few chords, just to see how it could handle the multiple touch a sect of piano playing. It worked well for a few chords, but after the 4th or 5th chords, the next chord I played didn't make any sound, so I waited, and I heard the chord about 2 seconds after I had taken my hand off the screen. So the chords obviously aren't flawless, but I expected that, as this is only an app, and not the real thing. The next thing I tested out was the split screen function (where you put two separate parts of the keyboard on the screen at once), and this worked well for some octave scales at a fairly slow pace, so I decided to see if this could handle chords on one had and some moving notes on the other. Unfortunately, it doesn't do so well, and kicked me out of the application several times, before I gave up on trying.
Other than this, I'd say this is a fairly good app for a beginner pianist who wants to improvise a little without making too much noise, or for children who are bored, but isn't suitable for the moderate to advanced player, which is to be expected.