There is considerable evidence that exposure to air pollution is harmful to health. In the USA, ambient air quality is monitored by Federal and State agencies for regulatory purposes. There are limited options, however, for people to access this data in real time, which hinders an individual's ability to manage their own risks. This paper describes a new software package that models environmental concentrations of fine particulate matter (PM2.5), coarse particulate matter (PM10) and ozone concentrations for the state of Oregon and calculates personal health risks at the smartphone's current location. Predicted air pollution risk levels can be displayed on mobile devices as interactive maps and graphs color-coded to coincide with Environmental Protection Agency air quality index categories. Users have the option of setting air quality warning levels via color-coded bars and are notified whenever warning levels are exceeded by predicted levels within 10 km. We validated the software using data from participants as well as from simulations, which showed that the application was capable of identifying spatial and temporal air quality trends. This unique application provides a potential low-cost technology for reducing personal exposure to air pollution which can improve quality of life, particularly for people with health conditions, such as asthma, that make them more susceptible to these hazards.