You generally won't offend others while on your cell phone while walking down the street or on public transportation, but taking or making a call at the movies or church? No way. Those are some of the findings of a new survey by the Pew Research Center on what Americans consider appropriate use of cell phones in public or social settings. Predictably, the study found a definite generational divide over cell phone use, with 90% of 18-to-29-year-olds finding it appropriate to use phones on public transportation, compared with 54% of respondents older than age 65. Some 50% of younger users found cell use at a restaurant acceptable, compared with 26% of their elders. The study reflects how technology is rewriting the rules of civility in a world in which 90% of the US adult population say they have a cell phone and 31% say they never turn it off.