For those of us who didn’t know; “Synesthesia is a neurological phenomenon in which stimulation of one sensory or cognitive pathway leads to automatic, involuntary experiences in a second sensory or cognitive pathway”, explains American neurologist Richard E. Cytowic in ‘The Man Who Tasted Shapes”, his second of many books on the subject. In other words, some people can actually taste the rainbow.

These people are few and far between (approx. ten in one million) and you’d probably already know if you were one, but in case you were wondering what it would be like, ROY G BIV is a new app from illustrator Julian Glander that turns colour into sound. The app takes colour data from your camera and converts it into modulations for an 8-note synth. Just hold up the phone to anything colourful and hear the phone play that colour’s sound. You can then control the attack, decay, oscillation and waveform of whatever you’re pointing your phone at.

This is not the first time we've seen apps creating music from non-figurative ideas. The Interactive Music Battle turns movement data into music in realtime.