Through a large-scale questionnaire survey of 6,210 individuals nationwide in Japan, the research study investigated how people's digital service usage and their online social interactions affect their residential location choice and urban structure.

The study revealed the following important findings:

• Age matters: Older people use less digital services, and the likelihood of relocating in urban areas decreases by 4.4% for every year they get older.
• Digital service usage and residential location choices: People who use more digital services (e.g., telework, online shopping) are more likely to relocate which can lead to changes in urban structures and demand for public services.
• Car ownership and digital service usage: People who own a car are 9% more likely to shop online than those who do not. Contrary to the common perception that digital services reduce travel, the study found that people who own a car do more online shopping. This may be related to the flexibility of driving to the store to check out products in advance and then purchasing them online at a lower cost.
• Online social networks: People who use more digital services tend to value online relationships such as social media rather than face-to-face relationships, which can affect social cohesion, disaster response, and community-based safety systems. These behavioral changes are not just about convenience, but they are reshaping urban infrastructure, social interaction, and the long-term sustainability of cities.
• Growing digital divide: older people and those living in rural areas are significantly less engaged in digital services, and as online services continue to expand, there is a risk that these groups will be isolated from society.

Mr. Mustafa Mutahari, PhD Candidate, and the main author of the study, stated, “Urban development must be both smart and inclusive. A digitally connected future is only sustainable if it’s equitable and supports diverse populations. Our research is strongly linked to SDG 11 (Sustainable Cities and Communities) and SDG 10 (Reduced Inequalities). Policymakers must balance the provision of digital services and physical services which require mobility. Overdependence on either can harm sustainable urban development. The future lies in integration, not replacement, and this is the path to achieving well-being, inclusion, and urban resilience.

As future research, the research team plans to develop a "quantitative trade-off model" to optimize the balance between digital and physical service usage. This model will quantitatively evaluate the impact of digital service substitution on urban structure, the social environment, and the quality of life of residents, with the aim of contributing to the development of sustainable and inclusive urban strategies.