The study is designed to help people aged 16 to 30 with Sickle Cell Disease (SCD), a condition where blood cells are sickle-shaped instead of round. This shape can cause pain by blocking blood flow. The study uses digital Cognitive Behavioral Therapy (CBT), a type of talk therapy that helps manage pain and stress. Participants will use the "CaRISMA app" on their phones to get therapy. Some will also get support from a peer, someone like them who understands what they're going through.

The study will test if using the app helps reduce pain and the need for pain medicine over a year. Participants will be divided into three groups: those using the app with peer support, those using the app without peer support, and those continuing with usual care.

• The study lasts for 12 months, with check-ins at 3, 6, and 12 months.
• Participants must have a mobile device and internet access.
• They must have frequent pain and be able to speak and read English.