Data about us as individuals is usually conceived of as something gathered about us, whether siphoned from our Facebook or requested by bureaucrats. But data collected and displayed by the tracking applications on our iPhones and Fitbits is material we collect by ourselves and for ourselves.

Well, maybe, says sociologist Gina Neff, who with Dawn Nafus (a senior research scientist at Intel Labs) wrote the recent book, Self-Tracking. In this Social Science Bites podcast, Neff tells interview David Edmonds that such information – your information -- is widely available to the device or software maker. Now combine that with social network data – and many apps essentially require you connect those dots – and what results is an unintentionally rich portrait of the user.  And that digital you, your doppelgänger, gets shared widely, whether you want it to or even if it’s an accurate depiction, at times making the difference in decisions of whether you worthy of that job or ought to be insured.

Neff said she thinks of tracking devices as a sort of “bait and switch,” since their outputs aren’t wholly your own. As anthropologist Bill Maurer has said, data doesn’t have ownership so much as having parents.

But Neff doesn’t approach smart devices as a Luddite or even that much of an alarmist; she bought first-generation Fitbit when they were brand new and virtually unknown (all of five years ago!). She approaches them as a sociologist, “looking at the practices of people who use digital devices to monitor, map and measure different aspects of their life.”

Many people with and without activity trackers feel they already track their lives – through a tally they keep in their head. Think of the item of clothing – say those ‘skinny jeans’ - you wear when you feel you’re particularly slim. “One of the things that motivated us in thinking about the book were these qualitative measures that help people understand their lives and give them a sense of tracking that is more empowering in some ways.” And one of the findings is that a low-common-denominator approach to the devices can prevent people from really taking control, or customizing the collection, of their own data. “For too many people,” Neff says, “they can’t access and control their own data on the devices in order to begin to frame the next question.”

Her findings on smart devices surprised her several times. For example, she explains, many of today’s digital artifacts are anchored in much older sociological practices. She cites Lee Humprheys’ examinations of how Twitter use lines up with how diaries were used in the 19th century: “Lo and behold, some of those same short entries – ‘Had breakfast late,’ ‘It rained today’ – that we think of as disposable and part of the digital era really are much older.”

Neff was also taken aback at who the audience is for self-tracking. “I thought I was going to study just these kind of geeky, West Coast, Silicon Valley, male types who wanted to engineer everything about their life. And boy, was I wrong.” Users are much more diverse, and often less self-absorbed; some people are using the devices to stay on top of medical concerns, and other just want to be more productive in everyday life. And their devotion can be ephemeral – Neff said studies find 60 percent of activity trackers get disused within six months.

Neff is an associate professor, senior research fellow, program director of the DPhil in information, communication and the social sciences at the Oxford Internet Institute. Self-Tracking, which reviewer Simon Head at The New York Review of Books described as “easily the best book I’ve come across on the subject,” is her third book. Earlier volumes were 2012’s Venture Labor: Work and the Burden of Risk in Innovative Industries, which won the 2013 American Sociological Association Communication and Information Technologies Best Book Award, and 2015’s Surviving the New Economy (with John Amman and Tris Carpenter).