This study examines the feasibility and acceptability of a mindfulness-based mobile intervention designed to support pain and sleep management among adolescents and young adults with sickle cell disease. Chronic pain and sleep problems are common in this population and can negatively affect daily functioning and quality of life. Participants will use a smartphone-based mindfulness program that includes structured modules and guided mindfulness exercises over an approximately 8-week period. The study aims to evaluate whether the intervention is feasible and acceptable for adolescents and young adults with sickle cell disease.