India has the dubious distinction of having 10 out of the 20 most polluted cities in the world. The number of government air quality monitoring stations in these cities, baring New Delhi (which has 12), are between 1 or 2 stations for a population of 1 to 2 million people. This is woefully inadequate. A new wave of Low-cost Particulate Matter sensors (PM2.5 and PM10 being the most harmful of the air pollutants) enabled with IoT technologies is empowering citizens and communities to participate in their own governance and policy making. IndiaSpend has built India’s first Independent, Real-time Air Quality Monitoring Network using indigenously built Low-cost IoT devices. The project was launched in December 2015 and is currently active in 6 cities of India (with 10 more cities coming online in the near future). The talk will cover lessons learned from the IoT architecture perspective and the current Fast Time-Series based APIs developed which has enabled a significant enhancement in the accuracy & scalability of the air quality data analysis.