Background: Mobile phones have become an integral part of children's daily lives. Children and adolescents are among the most frequent users, often spending extended periods on mobile devices. Excessive mobile phone use may adversely affect their neurodevelopmental, psychosocial, and physical well-being.

Objective: To assess the impact of mobile phone use among school-going children in Bangladesh.

Methods: This school-based cross-sectional study was conducted in preschool and primary schools of Dhaka City from November 2024 to April 2025. A total of 220 children aged 3–10 years who used mobile phones were enrolled. Data were collected using a pre-designed structured questionnaire after obtaining written informed consent from parents or legal guardians. Data were analyzed using the Statistical Package for the Social Sciences (SPSS) version 23.

Results: Nearly half (41.8%) of the participants were aged 6–8 years, and the majority were male (73.6%). Most children (60.0%) used mobile phones for 3–5 hours daily, with gaming being the primary purpose of use (81.8%). Social and behavioral problems were the most common developmental abnormalities, affecting 30.9% of children. Other developmental impairments included cognitive delay (10.9%), speech development impairment (8.6%), hearing problems (7.3%), and vision problems (1.8%). Regarding physical abnormalities, aggressive behavior was the most prevalent finding, reported in 81.9% of children, followed by dry eyes (72.3%), backache (63.6%), and headache (54.5%).

Conclusion: This study concludes that more than half children passed 3-5 hours by using mobile screen. Social and behavioral problems were the most common developmental concerns among children using mobile phones, while social & behavioral problem was the most frequent neurodevelopmental abnormality. The findings suggest that excessive mobile phone use may have adverse effects on the developmental, behavioral, and physical health of children. Increased parental supervision and appropriate screen-time regulation are recommended to promote healthy child development.

TBU..