This article argues that the forms of "public" subjectivity associated with cellular phones are defined as much by the positive valuations of cellular technology as by the negative ones. Furthermore, cellular publics depend upon a critique of a previous era's fixed-line telephony. All of this suggests that the material affordances of the devices which mediate public subjectivity are important. It also suggests that "publics" are inherently historical; users of "publics" have a sense of that public's natural history which, if undermined, create anxieties. This argument, based in part on material gathered in Brazil, facilitates the selection of four attributes of cellular publics which are grounded in concepts of time, space, and person: 1) the reduction of response time; 2) the transcendence of space; 3) the unification of communicative and mediating capacities into a single device; and 4) the increased portability of that device, making for its ubiquity in social and professional settings. It is the unity of these four attributes which, I argue, make cellular publics unique.