In the past few decades, digital technologies have profoundly altered virtually every aspect of human life. While the direct impact of digital technologies on individuals’ economic welfare or personal behaviors has attracted considerable attention, the interplay of digital technologies with social connections remains underexplored. Indeed, regardless of whether formed offline or online, social connections in the form of personal ties and affiliations that have long been the bedrock of human society continue to shape human behaviors and outcomes. To the extent that digitization will only continue to grow in scale and scope, an understanding of such effects is important for scholars, practitioners, and policymakers. I address two overarching research questions in my dissertation: (1) Whether, and to what extent digital technologies affect individuals’ economic welfare and habituated behavior, and (2) How social connections such as personal ties and affiliations condition the impact of the digital technologies.

My studies are conducted in two distinct contexts: mobile interventions for health, and computer ownership for social and economic welfare. Drawing on diverse bodies of literature and using various econometric methods, I seek to answer questions related to how interventions orchestrated on mobile platforms help individuals form healthy behaviors, and how computer ownership affects long-term income mobility. In the first essay, I show that a social norms intervention on a mobile platform is effective in increasing individuals’ physical activity. In the second study, I investigate how the motivational incentive of reciprocity can be leveraged to promote healthy behavior. Finally, in my third essay, I show that computer ownership generates both private and social returns (IT spillovers) on individuals’ income mobility. All three papers then consider how individuals’ social connections condition the direct effects of digital technologies. The first two studies explore how online social ties and social relationships moderate the impact of mobile interventions, and the third study examines how caste groups affect the positive spillover effects of computer ownership. Collectively, the three studies advance our understanding of the heterogeneous effects of digital technologies on individuals and provide implications for researchers and practitioners.