Today's users communicate via multiple apps, even when they offer almost identical functionality. We studied how and why users distribute their contacts within their app ecosystem. We found that the contacts in an app affect a user's conversations with other contacts, their communication patterns in the app, and the quality of their social relationships. Users appropriate the features and technical constraints of their apps to create idiosyncratic communication places, each with its own recursively defined membership rules, perceived purposes, and emotional connotations.
Users also shift the boundaries of their communication places to accommodate changes in their contacts' behaviour, the dynamics of their relationships, and the restrictions of the technology. Because the communication place affects who or what is allowed inside, it simultaneously pushes other contacts outside its boundaries. This ends up shaping the "placeness" of not one, but all apps in a user's app ecosystem.
We argue that communication apps should:
a) support creating multiple communication places within the same app, so users can create boundaries between groups of contacts within their favorite app,
b) relocating conversations across apps, to weaken the channel symmetry imposed by current communication app architectures,
c) and sharing functionality across apps, to avoid breaking boundaries in cases where users want to use the communication feature of one app with a contact that belongs to a different place