"It's our mutual responsibility to share": The Evolution of Account Sharing in Romantic Couples

While most online accounts are designed assuming a single user, past work has found that romantic couples often share many accounts. Our study examines couples' account sharing behaviors as their relationships develop. We conducted 19 semi-structured interviews with people who are currently in romantic relationships to understand couples' account sharing behaviors over the lifecycle of their relationship. We find that account sharing behaviors progress through a relationship where major changes happen at the start of cohabitation, marriage, and occasional breakup. We also find that sharing behaviors and motivations are influenced by couples' relationship ecology, which consists of the dynamics between the couples and the social environment they live in. Based on these findings, we discuss implications for further study to support couples' sharing needs at different relationship stages and identify design opportunities for technology solutions to facilitate couples' sharing.