Our research team has found that empathic traits have been declining among young people in the United States in recent years. Given that empathy is a fundamental building block for healthy social relationships, something must be done to prevent these changes. In the current project we aim to design an engaging, interactive, and effective smartphone application (app) with the purpose of teaching adolescents to have more compassionate and empathic characters. We define empathic character as a constellation of prosocial traits, motives, and behaviors. In a previous Templeton-funded grant (Wake Forest University, Psychology of Character) we found that young adults who received 2 weeks of daily empathy-building text messages had more empathic characters relative to those who received control messages. These results persisted 6 months later. In the current project, we will conduct a longitudinal experiment to examine whether adolescents who use the empathy-building app for one month (versus a control app) have higher empathy and compassion, more prosocial behavior (charitable donations, volunteering), and less aggressiveness (e.g. aggressive beliefs and behavior). After empirically evaluating the app?s efficacy, we will broadly disseminate it to a wide audience by offering it free of charge on iTunes and other platforms, in addition to typical scientific dissemination of the results (e.g. conference presentations, scientific papers). One novel aspect of our proposal is its interdisciplinary collaboration, spanning social science researchers from Psychology, Communication, and Social Work, and including an expert team of app development professionals who will create, evaluate, and market a high quality research-based app. This multidisciplinary academic-corporate partnership allows us to combine the most rigorous scientific designs with the most up-to-date and engaging technology. More empathic individuals can ultimately help to build a more empathic society.