RjDj uses the sensors, headphones & mic for the iPhone to create “reactive music” with the sounds of the world around you. The app captures audio from the environment with what they call “scenes” (made with Pure Data). Each scene is different, making various patterns or effects in response to where you are and what you’re doing. It’s sort of a psychedelic musical snapshot of what you hear in that moment, and you can record it and upload it for sharing.
Over year ago, RjDj recorded this video to show how they do what they do:
RjDj’s here in NYC to debut a new product, the RJC1000, which they say is their “take on the the legendary Akai MPC range. Think the MPC for reactive music and you know a lot.” They’ll also hold a holiday hack shop to teach everyone how to make reactive music. Make sure to bring all your toys if you want to register and attend: laptop, headphones, mic, iPhone/iPod.
All the info can be found on the RjDj pages. Have fun!