Desirable design: What aesthetics are important to young people when designing a mental health app?

<b>Objectives:</b> Smartphone apps can be highly effective in supporting young people experiencing mood disorders, but an appealing visual design is a key predictor of engagement with such apps. However, there has been little research about the interaction between visual design, mood and wellbeing in young people using a mental health app. This study aimed to explore young people's perspectives on colour and visual design in the development of a music-based app for mood management. <b>Methods:</b> Workshops were conducted with 24 participants (aged 13-25 years) with data analysis following a general inductive approach. <b>Results:</b> Results indicated that colour could impact wellbeing in both positive and negative ways. Participants favoured a subtle use of colour within sophisticated, dark palettes and were influenced by a complex interplay of common semiotic values, experiences with other apps, and mood. <b>Conclusions:</b> These findings highlight the highly contextual nature of the relationship between colour and mood, emphasising the importance of co-design in app development.