Yamaha and two partners have developed an iPhone application that lets up to 10 people play a piano at the same time, among other features.

Finger Piano Share is an iPhone application that was developed by Japan's Densan System. The application, which is still under development, allows users to play songs using virtual keys displayed on the screen of an iPhone or an iPod Touch. Like popular video games such as Guitar Hero and Dance Dance Revolution, Finger Piano Share uses a series of visual prompts to let users know what keys to press and when to press them.

The application can also be used to play a Yamaha MIDI-equipped piano that's connected to a computer with an Internet connection. When the user taps a key using Finger Piano Share, the note is played on the piano. Up to 10 people can use the application to play on the same piano, said Atsuko Ito, a supervisor at Yamaha's Center for Advanced Sound Technologies.

Finger Piano Share also supports Sekai Camera, a geotagging application developed by Tonchidot.

Using geolocation, Sekai Camera turns the iPhone's camera into a viewer that displays tags and files left behind by other users. The application supports Finger Piano Share, allowing users to upload music files that contain music played at a certain location or on a specific piano. Clicking on a music file offers the option to launch Finger Piano Share, which will then play back the music.