Prof. Kerr recently posted the results of an unscientific survey of user awareness of cell phone technology on the Volokh Conspiracy blog.
Take the unscientific results for what they are worth, but 95% of respondents indicated that they were aware that cell phone providers could obtain location data from cell phones.
In a previous post, I had criticized an aspect of a court decision from Texas about government access to cell phone tower data. I had pointed out that the decision contains an interesting discussion about whether cell phone users voluntarily convey their location to the cell phone company. As Prof. Kerr points out, this is significant from a Fourth Amendment perspective, because information voluntarily conveyed to third parties is not protected by the Fourth Amendment. This rule applies to, for example, banking records and phone numbers dialed.
I wrote: "While some people may be naïve about how cell phones work, I think there is a growing understanding that a cell phone user may be tracked either through cell tower information or the GPS device built into the phone."
This survey provides some – again, very limited – support for this assertion.