<p>Computational psychiatry offers promising opportunities for understanding and treating mental health disorders, yet achieving ecological validity—the accurate reflection of real-world experiences—remains a critical challenge. This perspective examines how digital health technologies can enhance ecological validity in computational psychiatry while addressing barriers in data collection, participant representation, validation, engagement, and methodological integration. We review key approaches, including digital phenotyping and adaptive design optimization, that enable more naturalistic data collection. However, achieving representative sampling and mitigating algorithmic biases remain unresolved challenges, particularly in AI-driven assessments. We discuss how expert-by-experience collaboration, systematic validation efforts, and structured open science practices can improve model generalizability and clinical applicability. Additionally, we explore the role of federated learning and edge computing in balancing privacy with robust, scalable model development. The paper concludes by integrating these challenges and solutions within a broader methodological framework, emphasizing the need for interdisciplinary approaches that bridge computational precision with real-world psychiatric care.</p>