28X is a free, privacy-focused digital health application designed to help women track their menstrual cycles, symptoms, and health insights with complete data privacy. The app operates entirely on the user's device, ensuring that no personal health data is stored in the cloud, shared, or sold. Built by women for women, 28X prioritizes ethical design, inclusivity, and accessibility—offering support for neurodivergent users and those with lower literacy levels. It is available in over 33 languages and aims to empower every woman globally with safe, reliable, and stigma-free menstrual health tools.