There’s not much that we can do about all the physical matter that’s been designed and built by someone else. It is the way it is. But with the advent of portable devices with GPS, a compass, and a network, we can now design a layer on top of the real world that can contain all kinds of new information, ideas, and experiences. This is called augmented reality. When most people use the term, they are talking about a visual experience. You hold up the camera of your smart phone and infographics overlay the image of the the thing right in front of you. But for my money, the best experience of augmented reality is auditory. Using the iPhone platform, RJDJ is exploring the next phase of music, called reactive music. Compositions coming out the headphones are completely unique, mixed in the smart phone, having incorporated data from the listeners environment.