Echobo is a networked music instrument where a number of people can play a collaborative music. A master musician can create a room and control chord progression of the music by building blocks and moving a cursor. Echo musicians can join the room and generate sounds based on the chord that the master musicians choose. There is no limit in the number of echo musicians. The more, the better. 

When all the sounds that mobile phones of echo musicians are layered, echobo will bring a unique musical texture. Echobo is designed for an audience participation in a music performance.