This literature review gives a glimpse into the emerging developmental stage of ‘digital adolescence’ and draws an integrative, multi-layered picture of the effects of smartphones and social networking technologies (SNTs) on adolescents’ well-being. On the positive side, adolescents can use the new technologies to gather social capital, maintain constructive interpersonal relationships, and seek help online. Similarly, adult caregivers can leverage SNTs for early detection and prevention of adolescents’ distress. On the negative side, excessive smartphone use may result in behavioral addiction, cognitive impairment, and emotional distress. A critical discussion of these ‘cyber-dangers’ is provided, along with a discussion of methodological shortcomings in the literature and recommended directions for future research.