While psychologists agree that individuals differ from each other on a variety of traits (e.g., personality), the theoretical and methodological assumptions used to develop pen and paper psychometric tests have failed to keep pace with recent computational developments that utilise digital traces to infer information about individuals and the world around them. For example, while self-report assessments are designed to predict behaviour in the absence of any real-world measure, digital devices (e.g., smartphones) have facilitated the measurement of many real-world outcomes (Piwek et al., 2016). Even the purchase of a specific device can reveal something about the individual behind the screen (Shaw, Ellis and Ziegler, 2018). Smartphones could therefore lead to a step change in how we study and conceptualise a variety of individual differences. This is particularly pertinent when it comes to understanding personality traits (e.g., levels of extraversion – a measure of sociability) that are automatically deployed in new situations seamlessly and non-consciously (Roberts and Hill, 2017).

A number of studies using smartphones have correlated data from these devices with traditional psychometric tests. However, following a brief review of this work, this chapter will question how much progress has been made in this domain. There remains a general consensus among many social scientists that, while traditional psychometric measures are far from perfect, they are the only option available. This chapter will challenge that assumption however, data derived from smartphone sensing may ultimately support the notion that existing psychometric tools remain valuable and reinforce existing conceptualisations of standard personality models.