Air pollution has become a severe problem in most of the world and is among the governments' prior subjects. In the present time, urban dwellers spend most of their time in confined spaces such as home, office, school, shopping malls, and gyms. Contaminant gases (CO2, CO, NO2) and particulate matters arising from occupant activities such as exercise, sleeping, cooking, smoking, and cleaning are among the most critical factors which influence indoor air quality. Such gasses and particulate matter depend on human activities lower indoor air quality; hence, they cause many serious health problems, especially respiratory tract, cardiovascular and dermatological diseases. In this study, the indoor air quality of housing is examined depending upon occupant activities. Air quality parameters of temperature, humidity, CO2, CO, PM10, NO2, which are collected from the bathroom, kitchen, living room and bedroom of the housing, are measured using 32-bit ESP32 controller and a set of air quality sensors Obtained air quality data is saved to cloud server by the help of mobile user interface developed through Blynk IoT platform. As a result of the analysis, it is observed that occupant activities like sleeping, shower, laundry, and cooking adversely affect indoor air quality.