play check

The app allows you to record music being played (though the room must be quiet as all sound is analysed). Edit the mistakes during recording then test yourself against the recording for accuracy. You can share tunes you have made via email or other upload mechanisms.
You can change the rhythm of the notes, compressing the time between each note.
If you don't want to record live music you can record a tune using the screen keyboard then test yourself against it either with the screen keyboard or by the app listening to you playing a real keyboard.