Even five years ago, personal data tracking was mostly a fringe activity, something you'd read about in Wired articles profiling lifeloggers that were forever coming up with new ways to gather and analyze data about their own lives. As those sensors shrank and came together in modern smartphones and sports gadgets like Nike+ and mixed with a flood of new, easy-to-use apps, data tracking has become increasingly mainstream. You've probably seen Nicholas Felton's gorgeous Personal Annual Reports that break down a year's worth of personal data into graphs, maps, and statistics (e.g. weddings attended, movies watched, cups of coffee consumed), and he just published his 2010/2011 Biennial Report. Named one of the 50 most influential designers in America by Fast Company, Felton recently joined the Facebook team and was instrumental in building Timeline. He took some time out of his busy schedule for 5 Minutes on The Verge, and you can follow him at @feltron and feltron.com.

Mac or PC (and all-time favorite computer, make and model)?

I've been using Macs since I was in 7th grade, when my mother brought home our first computer... a Mac Plus with a 30mb external hard drive. My favorite computer is whichever model is helping me get my work done today, but this Mac Plus may survive as the one I am fondest of.

What's the story behind you getting involved in Facebook? Did you take "the walk" with Mark Zuckerberg?

I received a message from Mark at the beginning of last year and began a conversation with him. A few months later, my Daytum partner and I came out to San Francisco for a couple of meetings including a trip to Facebook. The more we talked, the more we saw that our desire to make a platform for quantitative expression was aligned with what Facebook was building, and that we could have a much greater impact by joining their efforts.

What did you learn about yourself from your Annual Reports? Have they made a difference in your daily life?

The Annual Reports teach me something new each year. I have explored my habits and routines, how I am perceived by those around me and last year I learned much more about my father than I had ever known. For the 2010/2011 Report, I have investigated my habits with new levels of detail, but ultimately the macro behaviors are what amaze me. By tracking the same metrics across two years, I was able to measure very small changes in my life. For instance, I learned that while I am spending much more time in California now, my total time with friends and family has stayed fairly constant (a complete surprise).

The Reports once inspired me to be more adventurous and to say "yes" to activities that I would naturally decline as it might make for an interesting story at the end of the year. Now that they have become so ingrained in my behavior, I am far less likely to be swayed by their influence.

In general, I think the Reports have made me a much more aware of my routines and grateful when I can break from them.

What kind of gadgets / tools / habits do you use for the tracking?

My iPhone is my best tracking tool. I relied on iCal on the phone and my Mac for recording everything over the past two years. I currently have a custom iPhone app that is helping me record the year. I also rely on my Fitbit and have been using a Wifit scale.

Where is Facebook's design most lacking? Where does it work best?

One of the most difficult things about working on Facebook is that it needs to work for so many people on such a range of devices, screens, and browsers. These requirements can restrain what is possible. Thankfully, mobile devices today are powerful (enough) and unemcumbered by legacy browsers. This has had a liberating effect on the creativity of our designers, and is allowing for imaginative new interactions like Joey Flynn's integration of a live-view camera mode within the cover photo in the iOS app.

"In 2008 I was the only person I knew wearing a pedometer. Today half my friends are wearing FitBits. "

Personal data tracking, once relegated to a fringe group of people documenting their lives, is increasingly becoming mainstream. Do you still feel like an outlier with your yearly reports?

Less and less... in 2008 I was the only person I knew wearing a pedometer. Today half my friends are wearing FitBits. Whenever I have uncovered a new metric in my life I've always wanted to be able to give it context. It tickles my curiosity to quantify a habit of mine, but I would really love to see how I differ from or resemble my friends. This wish seems to be materializing more and more quickly each day.

Do you feel a need to disconnect?

I love a good break from the internet, but checking out from my data collection has not been the sort of break that I have wanted to take. Fortunately, I have found a way this year to significantly reduce my manual tracking, while maintaining a satisfactory degree of data-completeness.

What's the best book you've read lately?

I enjoyed "The Information" by James Gleick, but the last book I couldn't put down was "Blind Descent" by James M. Tabor about exploring the world's deepest cave systems.

What was the last time you were really stunned by a development in technology (e.g. launching Spotify for the first time, using the original iPhone, seeing sports in HD)?

I completely take it for granted now, but the screen on the iPhone 4 remains phenomenal. It was a given that over time our displays would approach the resolution of paper, but I never expected to see resolution quadruple overnight for the same price.

Who (or what) are you most excited about on the web these days?

I am truly excited about the Facebook Open Graph... this is the system by which song listens (and any other action) can be recorded, aggregated and shared. Being able to play a part in how this technology evolves is thrilling, and it's why I am working at Facebook.

Who's doing the most interesting work in the mobile app space?

The apps that interest me most are repurposing the hardware of mobile devices to make them work in ways that were never intended. I am thinking about the heartrate monitor app that uses the camera and flash to read the pulse in my finger or the wikisense app that uses the camera to measure radiation after you've covered the lens.

What were some of the biggest design hurdles with creating Timeline, a product for nearly a billion users across a huge range of languages and ages?

The most contested and complicated dimension of Timeline's design was determining how time compression would work. Understanding the distinctions between various models of expansion on posts, aggregates and highlights took an enormous amount of concentration. At one point we designed a prototype that could mimic all 16 options we were considering. This exercise helped to remove many options, but the mechanics remained in flux until we could get real data into our models.

Similarly, what kind of design concerns start to appear at that kind of scale and user involvement?

Yes, the scale is enormous, but I believe that designing a successful product for an audience this size is very similar to designing a successful product at any scale. Our goals include clarity, performance, and ease of use. These goals will help a new product be adopted by a broader audience and serve our existing users well.

What's your primary browser?

Safari.

How do you stay focused?

Music, caffeine, anxiety and an ability to find places and times to work when no one is around.

What movie are you most looking forward to in 2012?

I have a poor sense of what is being released, but if there's a Batman movie coming out, I will be there.

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Photo credit: Noah Kalina