Youth with one or more chronic diseases are at increased risk of further complications, disease, or even early death as they enter their adult years. Recent increases in both asthma and obesity among youth have led to high health care utilization, increased health-related complications, and expanded risks of subsequent cardiovascular disease burden. The research team will develop educational content in core areas (e.g., fatigue, physical activity) for Managing AsThma AnD Obesity Related Symptoms (MATADORS), an mHealth technology-enhanced nurse-guided intervention. Youth with asthma and obesity and their primary caregivers will participate in interviews to explore their perspectives on barriers, facilitators, needs, and preferences toward adopting health behaviors, medication adherence, disease awareness, symptom self-management behaviors, and utilization of a mobile smartphone platform. Additional details on content availability, delivery approaches, system needs, and functionality will be explored through semi-structured interview questions. Health care providers (physicians, nurses, nurse practitioners, dietitians, and respiratory and exercise therapists) will be invited to participate in interviews to seek their input on patient-caregiver needs, priority clinical focal areas, recommendations for symptom self-management, and preferences for intervention delivery. Interview findings will be used to inform intervention and app design. Providing youth with strategies to enhance symptom self-management may result in decreased symptom prevalence, improved quality of life, and long-term reduction of cardiovascular morbidity and mortality as they move into adulthood.