Air quality is a crucial aspect of the overall health of any ecosystem. Rapidly increasing urbanization and transportation have proven detrimental to the quality of the air we breathe. Nearly two-thirds of urban air pollution is caused due to vehicular emissions. The harmful pollutants released every day into the atmosphere are deteriorating the environmental and human health. Air pollution has been closely associated with climate change as well as some serious health issues. Hence there is an urgent need for consistent, large-scale air quality monitoring and mitigation strategies. In recent years, the Internet of Things, with its wide range of technologies and some distinct attributes like connectivity, sensing, analyzing and processing capabilities, scalability, and flexibility has provided the world with a dependable option to monitor air pollution in real-time. This paper discusses the key technologies which support IoT-enabled air pollution monitoring systems, proposed solutions, and the challenges faced in the deployment of real-time pollution monitoring systems.