Because Phyn does not have a flow sensor, it relies solely on pressure sensing to provide you with water use data. Phyn is able to detect which fixture is in use in your home based on the unique pressure “voice” of your bath, shower, etc... Phyn also provides the estimated amount of water used by that fixture by observing the characteristics of the pressure changes in your pipes while fixtures are being used, among other patented techniques. It provides ranges of use in the app, which will get narrower over time as the system gets more familiar with your fixtures and usage patterns.