Anything that is an external prosthetic device creates one into a cyborg. The idea of a cell phone being a technosocial object that enables an actor (user) to communicate with other actors (users) on a network (information exchange and connectivity) makes one into what David Hess calls low-tech cyborgs:
"I think about how almost everyone in urban societies could be seen as a low-tech cyborg, because they spend large parts of the day connected to machines such as cars, telephones, computers, and, of course, televisions. I ask the cyborg anthropologist if a system of a person watching a TV might constitute a cyborg. (When I watch TV, I feel like a homeostatic system functioning unconsciously.) I also think sometimes there is a fusion of identities between myself and the black box" (Gray, 373).
"According to the editors of The Cyborg Handbook, cyborg technologies take four different forms: restorative, normalizing, reconfiguring, and enhancing (Gray, 3). Cyborg translators are currently thought of almost exclusively as enhancing: improving existing translation processes by speeding them up, making them more reliable and cost-effective. And there is no reason why cyborg translation should be anything more than enhancing". Source: Cyborg Translation
I'd additionally define two additional types of cyborgs based on consumptive practices: those who attach prosthetics as a necessity, and those who attach them as an external representation of status and tribal affiliation. In the latter case, one's external prosthesis is chosen carefully and updated frequently. This is most often seen in middle classes, especially in the young offspring of these classes.
1. Cyborgs actually do exist; about 10% of the current U.S. population are estimated to be cyborgs in the technical sense, including people with electronic pacemakers, artificial joints, drug implant systems, implanted corneal lenses, and artificial skin. A much higher percentage participates in occupations that make them into metaphoric cyborgs, including the computer keyboarder joined in a cybernetic circuit with the screen, the neurosurgeon guided by fiber optic microscopy during an operation, and the teen gameplayer in the local videogame arcarde. "Terminal identity" Scott Bukatman has named this condition, calling it an "unmistakably doubled articulation" that signals the end of traditional concepts of identity even as it points toward the cybernetic loop that generates a new kind of subjectivity (Gray, 322).
2. This merging of the evolved and the developed, this integration of the constructor and the constructed, these systems of dying flesh and undead circuits, and of living and artificial cells. have been called many things: bionic systems, vital machines, cyborgs. They are a central figure of the late Twentieth Century. . . . But the story of cyborgs is not just a tale told around the glow of the televised fire. There are many actual cyborgs among us in society. Anyone with an artificial organ, limb or supplement (like a pacemaker), anyone reprogrammed to resist disease (immunized) or drugged to think/behave/feel better (psychopharmacology) is technically a cyborg. The range of these intimate human-machine relationships is mind-boggling. It's not just Robocop, it is our grandmother with a pacemaker (Gray, 322). - George P. Landow, Professor of English and Art History, Brown University.
In "Cyborgology: Constructing the Knowledge of Cybernetic Organisms" -- the introduction to the (Gray, Introduction), four classes of cyborg are described:
The latter category seeks to construct everything from factories controlled by a handful of "worker-pilots" and infantrymen in mind-controlled exoskeletons to the dream many computer scientists have-downloading their consciousness into immortal computers (Gray, 3).