Depression affects a large percentage of young adults across the globe. The delivery of mental health information and the provision of tools for the self-assessment of mood are important means in addressing this problem. While self-assessment of mood is becoming more common through web resources and mobile applications, existing resources are limited in multiple ways. First, they typically include a significant language component and are therefore not suitable to youth with limited literacy/speakers of other languages. Second, existing tools are not visually engaging, usually constituting questionnaires presented on monochromatic background. Third, existing tools are limited in their clinical validity. This paper presents the background to the creation of a prototype mood self-assessment tool delivered via a mobile app. Based on a clinically validated mood self-assessment measure, the prototype guides the user through 21 pictorial questions and provides overall feedback. The user’s level of engagement is assessed using data provided by Google Analytics and compared to their engagement with, and response to, the standard written self-assessment questionnaire.