Introduction On average, most youth apps only last 2 weeks, and the average lifespan of a youth mental health app can vary widely depending on several factors, including the quality of the app, market demand, competition and ongoing support and updates. Successful app development and scaling is rare and hinges on a combination of strategic planning, user-centered design and iterative improvement and investments over time. In 2020, Foundry developed the Foundry BC platform to deliver virtual integrated youth services to complement the existing in-person services provided in communities across British Columbia (BC). The platform consistents of an android app, IOS app, and Website compotents. This presentation will demonstrate the Foundry BC platform and discuss the keys to successful scaling, evaluation, engagement and innovation. We will also describe the function of the platform for youth, caregivers, service providers and administrators. Experiences: Based on the last four years, over 40,000 youth and caregivers across BC have registered on the Foundry BC platform. Key factors to successful implementation of the platform include a clear understanding of the target market and user needs (including youth, caregivers, service providers and administrators), extensive listening and engagement to ensure the creation of meaningful, evidence-based and intuitive content, as well as technological expertise to ensure responsive innovation. Agile change management methodologies has allowed our team to iteratively develop and rapidly adapt to user feedback, enhancing product relevance and usability. This includes ongoing refinements of the product’s design elements (e.g., interactive features, gamification, sharing of personalized content), and having strong leadership to monitor a regular feedback loop and iterative improvements based on user input, including youth from diverse communities and backgrounds. Robust technical and engagement infrastructure has been essential for scalability, ensuring that the Foundry BC platform can handle increasing user demands without compromising the care provided to youth or slowing service provider efficiency. Communication strategies and end-user training tactics have been crucial for reaching a broad audience and driving uptake across the province. Finally, this presentation will describe the importance of ongoing data analysis, evaluation and performance monitoring to facilitate informed decision-making and optimization of the platform potential across the network. Conclusions: By integrating engagement, technology, evaluation and change management elements, our team has been able to create an impactful platform that continues to be successfully scaled up across BC. Effective development and scaling strategies of youth-centred apps need to carefully consider effective engagement strategies of all users over time, enhancing its utility and satisfaction. Furthermore, high levels of engagement and change management throughout the development and scaling processes is critical to develop a product that resonates with the current needs of its audience and supports youth and caregivers in achieving health and wellness goals over time.