Temporal distribution and contextual variation of the impact of smartphone app usage on travel using one-week app-use diary in Indonesian cities

Evidence shows the significant influence of smartphone apps on travel behaviour, offering alternative avenues for activity engagement across diverse purposes and timeframes. However, the organisation of activities through smartphone apps differs significantly from physical activities due to their unique nature. This study aims to explore the temporal distribution and contextual variation of the impact of smartphone app usage on travel within multi-day and multi-purpose frameworks. In this study, a one-week app-use diary was gathered from 1,193 smartphone users in four urban areas within Indonesian cities and analysed using hurdle regression and mixed-logit models. The findings reveal that individuals predominantly use apps for leisure, with the impact of generating new activities/trips (generation effects) reported three times greater than reducing travel needs (substitution effects). This indicates that app activities primarily contribute to the creation of new activities. Furthermore, wealthier and male users exhibit a higher tendency to engage in app activities that generate new trips, while daily substitution effects are less prevalent among users in larger cities or those living alone. The varied purposes of app activities result in varied impacts on activity participation across different contexts. Maintenance activities, such as online shopping, tend to influence travel in multiple ways, with substitution effects greater than generation effects. Temporal factors, such as time of day and day of the week, shape the impact of app activities on travel. At noon and in the afternoon, app usage has multiple effects on activity-travel patterns, where the substitution of existing activities tends to outweigh the creation of new ones. Substitution effects in leisure activities are most likely to occur at night. On weekends, substitution effects are more likely to occur on Saturdays due to increased activity levels compared to Sundays. These findings suggest several policy recommendations to anticipate and manage the impact of app activities on urban travel.