On Jan. 9, 2007, 10 years ago today, Steve Jobs formally announced Apple's "revolutionary mobile phone" — a device that combined the functionality of an iPod, phone and Internet communication into a single unit, navigated by touch.
It was a huge milestone in the development of smartphones, which are now owned by a majority of American adults and are increasingly common across the globe.
As smartphones have proliferated, so have questions about their impact on how we live and how we work. Often the advantages of convenient, mobile technology are both obvious and taken for granted, leaving more subtle topics for concerned discussion: Are smartphones disturbing children's sleep? Is an inability to get away from work having a negative impact on health? And what are the implications for privacy?
But today, on the 10th anniversary of the iPhone, let's take a moment to consider a less obvious advantage: the potential for smartphone technology to revolutionize behavioral science. That's because, for the first time in human history, a large proportion of the species is in continuous contact with technology that can record key features of an individual's behavior and environment. To quote a recent article published in Perspectives in Psychological Science: "Psychology has a great deal of data on what people believe they do... but little data on what people actually do."
Researchers have already begun to use smartphones in social scientific research, either to query people regularly as they engage in their normal lives or to record activity using the device's built-in sensors. These studies are confirming, challenging and extending what's been found using more traditional approaches, in which people report how they behaved in real life or participate in relatively short and artificial laboratory-based tasks.
To illustrate the use of smartphone-based data collection, consider a forthcoming study that combined queries embedded in everyday life with sensor data to paint a more accurate picture of how mood is affected by a person's location. The data for the study came from more than 12,000 members of the general public who downloaded a free Android app to participate in the research. Twice during the day, they were prompted to report their mood and location, with location information additionally collected from the phone's location sensors. Using both kinds of location data, the study found that people reported significantly more positive moods in locations that typically involve social interactions (such as a café or friend's house) than at home, and more positive moods at home than at work.
Other studies have used sensor data to draw more subtle kinds of inferences. For instance, a study published in 2015 followed 48 students over the course of a 10-week school term. Using a combination of location, activity and audio sensors, the researchers could infer students' patterns of class attendance, study time, physical activity and socializing. These variables, in turn, predicted student GPA with surprisingly high accuracy. Another 2015 study used mobile phones to track 40 adult participants over a two-week period. Using patterns of movement and phone usage, the researchers were able to identify behaviors that predicted symptoms of depression.
These studies are just first steps. As more data are collected and methods for analysis improve, researchers will be in a better position to identify how different experiences, behaviors and environments relate to each other and evolve over time, with the potential to improve people's productivity and wellbeing in a variety of domains. Beyond revealing population-wide patterns, the right combination of data and analysis can also help individuals identify unique characteristics of their own behavior, including conditions that could indicate the need for some form of intervention — such as an uptick in behaviors that signal a period of depression.
Smartphone-based data collection comes at an opportune time in the evolution of psychological science. Today, the field is in transition, moving away from a focus on laboratory studies with undergraduate participants towards more complex, real-world situations studied with more diverse groups of people. Smartphones offer new tools for achieving these ambitions, offering rich data about everyday behaviors in a variety of contexts.
So here's another way in which smartphones might transform the way we live and work: by offering insights into human psychology and behavior and, thus, supporting smarter social science.
Tania Lombrozo is a psychology professor at the University of California, Berkeley. She writes about psychology, cognitive science and philosophy, with occasional forays into parenting and veganism. You can keep up with more of what she is thinking on Twitter: @TaniaLombrozo