Borderline is a sound mapping tool for iOS that uses urban sound to create new understandings of place. Using algorithms trained to identify ~100 common sounds, the project enables users to map sounds in their environment and place them in dialogue with other forms of urban data. The tagged recordings play back in their original locations, which creates an interactive acoustic footprint that changes as you move among them.

‘Borderlines’ are invisible boundaries that affect social and economic mobility in urban spaces. They appear whenever there is a difference in income, stability, or other forms of demographic information, and when combined with local sounds, they illuminate important intersections between sound, place, and power. 

These maps illustrate the percentages of renters living in Kitchener, Waterloo and Cambridge, and the percentage of renters who spend more than 30% of their income on housing. The borderlines show the difference in after-tax income between neighbouring areas. The larger the borderline, the greater the difference in income. 

During CAFKA, Thompson and her research team will lead a series of soundwalks through downtown Kitchener using the Borderline mobile app.