Synthetic musical instrument with performance-and/or skill-adaptive score tempo

An apparatus comprising:

• a portable computing device having a multi-touch display interface;
• and
• machine readable code executable on the portable computing device to implement the synthetic musical instrument, the machine readable code including instructions executable to present a user of the synthetic musical instrument with visual cues on a multi-touch sensitive display of the portable computing device, the presented visual cues indicative of temporally sequenced note selections in accord with a musical score, wherein the presentation of visual cues is in correspondence with a target tempo;
• and
• the machine readable code further executable to capture note sounding gestures indicated by the user on the multi-touch sensitive display and to repeatedly recalculate a current value for the target tempo throughout a performance by the user and thereby vary, at least partially in correspondence with an actual performance tempo indicated by the captured note sounding gestures, a pace at which visual cues for successive ones of the note selections arrive at a sounding zone of the multi-touch sensitive display.

A method comprising:

• using a portable computing device as a synthetic musical instrument, wherein the portable computing device includes a communications interface;
• presenting a user of the synthetic musical instrument with visual cues on a multi-touch sensitive display of the portable computing device, the presented visual cues indicative of temporally sequenced note selections in accord with a musical score, wherein the presentation of visual cues is in correspondence with a target tempo;
• capturing note sounding gestures indicated by the user using the multi-touch sensitive display;
• repeatedly recalculating a current value for the target tempo throughout a performance by the user and thereby varying, at least partially in correspondence with an actual performance tempo indicated by the captured note sounding gestures, a pace at which visual cues for successive ones of the note selections arrive at a sounding zone of the multi-touch sensitive display;
• transmitting an encoded stream of the note selection gestures via the communications interface for rendering of the performance on a remote device;
• geocoding the transmitted gesture stream;
• and
• displaying a geographic origin for, and in correspondence with audible rendering of, another user's performance encoded as another stream of notes sounding gestures received via the communications interface directly or indirectly from a remote device.