By Dr. Priyom Bose, Ph.D. Reviewed by Lauren Hardaker May 21 2026 A large Korean adolescent study links problematic smartphone dependence with higher odds of lifetime drinking and smoking, raising new questions about how digital behaviors, reward-seeking, and substance-use risks may cluster during teenage development. Study: Association between smartphone overdependence and alcohol and tobacco use behaviors among adolescents in Korea . Image Credit: Zwiebackesser / Shutterstock A recent