UNICEF Indonesia and UNICEF Mongolia, with UNICEF’s East Asia and Pacific Regional Office are building on existing technology solutions from the current market to ethically deliver cycle tracking and menstruation information to adolescent girls. Oky is a period tracker app, designed through co-creation with girls, for girls. It aims to transform stress and shame into empowerment, by delivering evidence-based information that is accessible on the digital tools girls use every day, delivered straight into girls’ hands, to help them make informed decisions about their reproductive health. Oky’s key features are built out in a very different way to other period trackers, built specifically for adolescent girls using an entertaining, integrated cross-breed of styles, and with a core focus on data privacy. Features include a predictive algorithm for tracking cycles, a data summary profile with a visual display of historical summaries, a menstruation information section with FAQs, quizzes and gamified components, and an AI chatbot. The user experience is girl-centred, with opportunities for users to choose avatars and themes, and with a gamified feel that encourages continued use through a Tamagotchi-style experience.