What role does cost play in shifting usage from one communications channel to the other? "Cost does play a role, but it's not absolute," says Stefana Broadbent, an ethnologist working for Swisscom Innovations. She cites as evidence the fact that we use cell phones from home although it's more expensive and we have alternatives available. The cost is offset by convenience.
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This expanded communication environment raises some questions: Are people "specializing" their use of different communication channels? For example, do mobile-phone, fixed-line, and e-mail users differentiate their usage of those tools in terms of content, communication partners, and habits? Are new channels affecting how existing channels are used?

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Stefana Broadbent, an ethnologist working for Swisscom Innovations, a division of Swisscom, Switzerland's largest telecom operator, says the answer to each of these questions is yes.

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Personally I use my cellphone quite a lot, in addition to email. The matter of urgency and the level of quality of the answer depends on which I choose.

If I have a question that I want a detailed answer to, I send an email, but if I just want a prompt yes/no answer from an acquaintance I send an SMS message or call the person.