How We Use Together: Coordinating Individual Preferences for Using Shared Devices at Home

Smart home devices increasingly aim to offer personalized experiences based on individual usage patterns and preferences. However, individuals in multi-person households often find themselves navigating daily life by coordinating with other members. This article aims to understand how users align their preferences for shared technology and their expectations for future smart homes in such contexts. To this end, we conducted a 7-day diary study and in-depth interviews to observe how members of multi-person households coordinate their preferences in everyday life. We discovered that members' device usage is not solely influenced by their own preferences, but is significantly affected by the preferences and social contexts of other members. We identified three strategies for coordinating preferences: coordination according to shared priorities, coordination according to shared rules, and coordination for relationships. Participants expected future smart homes to support their coordination needs. We propose design implications for multi-user smart homes that support coordination.