Track Air Quality - PM2.5 is a free iPhone application developed by Quang Huy Vo. It falls under the Lifestyle category and specifically the Health & Fitness subcategory. The app utilizes your GPS location to determine the levels of air pollution at the nearest available air quality measuring station.

The main features of Track Air Quality - PM2.5 include the ability to check real-time Air Quality Index (AQI) for your current city, display up-to-date AQI data for the selected location, and share this information with your friends and family. The app categorizes air quality levels into different colors to help you understand the health risks associated with each level.

Green signifies AQI, indicating good air quality with little to no risk. Yellow represents AQI, indicating moderate air quality with a slight health concern for sensitive individuals. Orange indicates AQI, which is considered unhealthy for sensitive groups. Red signifies AQI, where everyone may begin to experience health effects, and purple represents AQI, indicating very unhealthy conditions. Finally, brown signifies an AQI of 300 or higher, which is considered hazardous and may result in serious health effects.