Right age for cellphones?

The age group more and more parents are asking about is 8-to-12-year-olds, "the fastest-growing segment of the US cellphone market," the Houston Chronicle reports (already, 72% of 13-to-17-year-olds have mobile phones). The Chronicle cites experts as saying that, generally children around 10 or 11 can handle responsible use of a cellphone. But it really does depend on the child. Some of the signs of responsibility the Chronicle suggests are whether a child can remember to: charge the phone, turn it on before going out without prompting, and follow both family and school rules associated with cellphone use. Downsides to consider are: the bills kids can "rack up ... through texting and downloading songs" (remember to either to use your cellphone company's flat-rate, unlimited texting add-on or have it turn off texting altogether); unwanted calls and messages from peers or adults you don't know ("but kids shouldn't automatically ignore calls from numbers they don't know because it could be a parent themselves that's stuck and calling from another phone"); and "phones may give children privacy that parents don't necessarily want them to have." Very helpful things to consider. [NetImperative.com recently published a survey on how mobile social networking works, but the site has been having some server issues, apparently, so this link may not work.]