Systemic MCAS is a free iPhone application in the Lifestyle category, specifically catering to Health & Fitness. The app is designed to provide essential information about systemic mast cell activation syndrome. Users can access details on symptoms, diagnostics, therapy, salicylate intolerance, histamine intolerance, and recipes. The app offers guidance on following a grace diet to manage histamine levels, including food groups to avoid. Additionally, users can find support options for coping with the disease, such as seeking help and assistance when needed.

Moreover, Systemic MCAS features a contact form for user inquiries and a nutrition diary for tracking food and medication tolerability. It aims to empower users with comprehensive information about the condition, allowing them to stay informed, share insights with family and friends, and stay updated on the latest developments regarding MCAS.