This study assessed the interrelationships between smartphone use habits, self-reported dependence and mental health in a cross-sectional study encompassing 1,031 teenagers. The study variables comprised smartphone use/abuse and psychiatric distress signs/symptoms, whose associations were analyzed employing a structural model through structural equation modeling. Early smartphone use by teenagers was negatively and significantly associated to smartphone dependence scores (direct effect) and psychiatric distress symptoms (indirect effect), mediated by cell phone dependence. Furthermore, smartphone addiction led to increased psychiatric distress scores, with a large effect. Thus, it appears that the relationships between smartphone use/abuse and mental health are complex and require further studies to support interventions aimed at teenagers.