I just re-read the question below and realized that it was in reference to texting and not calling. Sorry for the mis-reading. We also collected some data on the distance to between interlocutors (if you can call them that) with regards to texting. Again, the sample is not generalizable but we found that only about 1% of text messages were reported sent to people who were in the same room. 12% of messages were reported sent to people in the same building, 2% sent to people who were outside but within eyesight. 42% were sent to people who were not immediately present but within 5 miles. 17% were sent to people who were between 5 and 30 miles and 26% to people more than 30 miles away. These are all rounded so they only add up to 99%. They are also a convenience sample so there is really no generalizability. I know that the distance between interlocutors was asked on the Pohs study at Michigan (a sample of respondents from the US) but that did not include those who were in the same room etc. Distance between interlocutors was also asked about in the EURESCOM p903 study from 2000 for a random sample of people in 9 European countries (about 1000 persons per country). Thus it has been a question that has been of interest. The EURESCOM work is described in the article: Smoreda, Z and Thomas, F. 2001. "Social networks and residential ICT adoption and use." in EURESCOM Summit 2001 3G technologies and applications. Heidelberg: EURESCOM. With reference to the use of texting among deaf persons there is an article by Frøydis Bakken: Bakken, F. 2005. "SMS use among deaf teens and young adults in Norway." Pp. 161 - 173 in The inside text: Social, cultural an design perspectives on SMS, edited by R. Harper, et al. Dordrecht, Netherlands: Springer. Rich L.