He has pioneered the study of digital anthropology and especially ethnographic research on the use and consequences of social media and smartphones as part of the everyday life of ordinary people around the world.
With Miller's students he has applied these ideas to many genres of material culture such as clothing, homes, media and the car, through research based on the methods of traditional anthropological ethnography in regions including the Caribbean, India and London.
In the study of clothing, his work ranges from a book on the Sari in India to more recent research explaining the popularity of blue jeans and the way they exemplify the struggle to become ordinary.
His initial work on the consequences of the internet for Trinidad was followed by studies of the impact of mobile phones on poverty in Jamaica and more recently the way Facebook has changed the nature of social relationships.
He has also carried out several projects on female domestic labour and being a mother, including studies of au pairs, and Filipina women in London and their relationship to their left behind children in the Philippines.
The study was based on ethnographic data collected through the course of 15 months in China, India, Turkey, Italy, United Kingdom, Trinidad, Chile and Brazil.
From 2017-2022 Miller directed a second five-year project, The Anthropology of Smartphones and Smart Ageing (ASSA), which consisted of ten simultaneous ethnographies in Brazil, Cameroon, Chile, China, Japan, Al-Quds (East Jerusalem), Ireland, Italy and Uganda.