Sociodemographic Associations With Early Smartphone Ownership in US Adolescents

Smartphones are a normative part of adolescent daily life. Most youth enter smartphone ownership between ages 10 and 12 years in the US,1 yet there is variability across individuals. There are benefits and risks associated with early smartphone ownership and use. Although smartphones offer social opportunities, they can also detract from the quality of in-person interactions.2 Further, smartphones can expose youth to inappropriate content and cyberbullying, can interfere with sleep, and may negatively impact mental health and impulsivity.3 Given recent legislation regarding a minimum age for social media use, it is of interest to understand the sociodemographic factors related to the age of smartphone ownership. This study leverages a large national dataset to examine sociodemographic predictors of first smartphone ownership age in adolescent youth.The ongoing ABCD Study collected demographic and screen use data (among other domains) from 11 878 children and primary caregivers at baseline (mean age = 9.9 years) beginning in 2016 with annual follow-up assessments.4 The analytic sample included all participants with complete data (N = 9475). Parents reported sociodemographic information at baseline. Parents were asked each year at what age their child received their first smartphone.4 Mplus version 8.3 was used for analyses.5 Descriptive statistics compared sociodemographic characteristics across smartphone ownership timing. We then estimated a cross-sectional multivariable logistic regression model to examine associations between key sociodemographic predictors (sex, race/ethnicity, household income, household structure, and parental education)6 and first smartphone ownership age. Race/ethnicity variables were included because the purpose of this study was to identify disparities by sociodemographic factors, and prior studies show variability in technology use patterns in youth based on this social construct.7 Self-reported categories were based on survey responses. We assessed multicollinearity via variance inflation factors (VIF > 5). Early smartphone ownership (<10 years old) was modeled as a binary outcome with odds ratios (ORs) greater than 1 indicating higher odds of early ownership. This cutoff was based on prior studies showing youth receive smartphones near the age of 10 years on average.1 Analyses applied Adolescent Brain Cognitive Development (ABCD) propensity sampling weights and used cluster-robust SEs with family ID as the clustering unit to account for twins/siblings. Statistical significance was defined as a P value less than .05 and testing was 2 sided.Descriptive statistics (Table 1) showed that the mean age of smartphone ownership was 10.9 years old and only 4% of youth were without a smartphone by the age of 14 years. In multivariable logistic regression (Table 2), adjusted odds of early ownership (<10 years) were highest for Black (OR = 3.01; 95% confidence interval [CI], 2.50–3.64), multi-racial/ethnic (OR = 1.79; 95% CI, 1.45–2.20), and Hispanic (OR = 1.41; 95% CI, 1.18–1.70) relative to white youth. Youth living with a single parent (OR = 2.09; 95% CI, 1.77–2.46) or cohabiting partners (OR = 2.11; 95% CI, 1.64–2.71) were more likely to experience early smartphone ownership, compared with living with married parents. Lower parental education (<bachelor’s degree) was also associated with higher odds (OR = 1.72; 95% CI, 1.46–2.02) of early smartphone ownership. Finally, girls were more likely to demonstrate early smartphone ownership than boys (OR = 1.41; 95% CI, 1.24–1.60). The maximum VIF was 1.3, indicating minimal multicollinearity among predictors and that variance inflation was well below conventional concern thresholds.The present study documents sociodemographic correlates of early smartphone ownership using data from a large demographically diverse cohort of US adolescents. Consistent with prior evidence,1 children from historically marginalized or structurally disadvantaged groups received their first smartphone before the age of 10 years. Conversely, adolescents with higher parental education level, with married parents, and of a non-minority race/ethnicity tended to delay ownership. These patterns persisted after mutual adjustment.Our results extend prior studies linking lower socioeconomic status to technology use.8 Early ownership may reflect greater perceived utility (eg, safety monitoring in single-parent or lower-resource contexts) and reduced parental gatekeeping capacity. Yet, young smartphone owners may also face higher exposure to online risks such as cyberbullying and sleep disruption.Study limitations include operationalization of smartphone ownership age (eg, integer rounded and dichotomized), a simplified list of independent variables, and the cohort’s enrollment period, which may reflect earlier smartphone norms. Future analyses using more current cohorts are needed to test interactions to identify contemporary conditional effects. Despite these limitations, this study provides a baseline for how family and socioeconomic factors relate to early smartphone ownership. These findings underscore the need for policies, guidelines, and parental education emphasizing early training in safe and responsible smartphone use, particularly in historically marginalized populations.Data used in preparation of this article were obtained from the 5.0 data release of the Adolescent Brain Cognitive Development (ABCD) Study (https://abcdstudy.org), previously held in the NIMH Data Archive. This is a multisite, longitudinal study designed to recruit more than 10 000 children aged 9 to 10 years and follow them over 10 years into early adulthood. The ABCD Study is supported by the National Institutes of Health and additional federal partners under award numbers U01DA041048, U01DA050989, U01DA051016, U01DA041022, U01DA051018, U01DA051037, U01DA050987, U01DA041174, U01DA041106, U01DA041117, U01DA041028, U01DA041134, U01DA050988, U01DA051039, U01DA041156, U01DA041025, U01DA041120, U01DA051038, U01DA041148, U01DA041093, U01DA041089, U24DA041123, and U24DA041147. A full list of supporters is available at Federal Partners—ABCD Study (https://abcdstudy.org/about/federal-partners/). We wish to thank all the research staff for designing the study, collecting, and preprocessing data, as well as the children, parents, teachers, and schools who participated in this multisite, longitudinal study.