Concept sketch for a persistent location based ambient sound layer. The ambient sound layer will leverage location data (google maps, directions), photographs (Flickr, Twitpic etc), text (blog posts, wikipedia, annotation, comments via Twitter). The ambient sound layer is designed for mobile devices. Relationships between sound recordings can be created (For example, the same type of sound at different locations). Time specific recordings can also be located on the layer (For example, the sound of something last month, year or decade). So far the ambient sound layer is just a concept.