Rosey started as a grocery list. My wife and I kept losing track of which phone the list was on. So I built a number we could both text, a shared little assistant that just remembered. Once it remembered groceries, it was a small step to remembering the wifi password, the pediatrician's number, what we usually buy at our grocery store, what the plumber said. From there, the obvious idea: this is the household's context layer, the thing that knows the shared facts so neither person has to be the one who remembers.