Problematic smartphone use may be associated with adolescent emotional and behavioral difficulties through impaired self-regulation, night-time engagement and sleep disruption. Objective: To examine the association of problematic smartphone, use with behavioral difficulties and evaluate sleep and family factors. Materials and Methods: In this analytical cross-sectional study, 400 school-going adolescents aged 10–19 years completed the SAS-SV, Strengths and Difficulties Questionnaire (SDQ), Pittsburgh Sleep Quality Index (PSQI), and questionnaires on smartphone, family, academic and lifestyle factors. Associations were examined using chi-square tests, Spearman correlation, bootstrap mediation analysis and multivariable logistic regression. Results: Abnormal SDQ total difficulties were present in 20.0%, while 17.0% were borderline. Adolescents with PSU had higher odds of abnormal total difficulties than those without PSU (33.8% vs 12.9%; OR 3.46, 95% CI 2.08–5.73). Associations were strongest for hyperactivity/inattention (OR 3.03) and emotional symptoms (OR 2.62). The SAS-SV score correlated with SDQ total difficulties (ρ=0.42). Poor sleep was present in 45.0%; night-time smartphone use was associated with poor sleep (OR 4.08, 95% CI 2.68–6.20). Sleep accounted for approximately 31% of the association between SAS-SV and SDQ scores. In adjusted analysis, PSU (AOR 2.41), poor sleep (AOR 2.06), low parental monitoring (AOR 1.94) and night-time use (AOR 1.78) remained significant predictors, whereas daily use >4 hours did not. Conclusion: Behavioral difficulties were associated more strongly with problematic and night-time smartphone-use patterns than with duration alone, with sleep and parental monitoring representing important correlates.

Smartphone use is now embedded in adolescent education, communication and recreation, but patterns characterized by prolonged use, frequent checking, night-time engagement and impaired control may be clinically relevant. Objective: To describe smartphone-use patterns and estimate the prevalence of problematic smartphone use (PSU) among school-going adolescents. Materials and Methods: An analytical cross-sectional study included 400 adolescents aged 10–19 years selected by multistage stratified random sampling. A self-administered questionnaire assessed sociodemographic characteristics, daily duration, night-time use, checking frequency, age at first use and primary purpose. PSU was assessed with the Smartphone Addiction Scale–Short Version (SAS-SV), using sex-specific cut-offs. Descriptive statistics and chi-square tests were used. Results: Mean age was 15.2 ± 2.4 years; 53.0% were male. Overall, 39.0% used smartphones for >4 hours/day, 47.0% reported use after 10 pm on at least four nights/week, 33.0% checked their phone >50 times/day, and 29.0% began smartphone use before age 10. Social media (35.0%) and gaming (24.0%) were the most common primary purposes. PSU was present in 34.0% (95% CI 29.4–38.6%). Prevalence increased from 21.4% at 10–13 years to 41.7% at 17–19 years (p=0.003), while the difference by sex was not significant (p=0.211). Conclusion: Approximately one-third of adolescents met SAS-SV criteria for PSU. Older age, frequent night-time use and predominantly recreational patterns highlight the need to assess how and when adolescents use smartphones, rather than relying on total screen time alone.