There are many apps that help women with tracking their monthly cycles. However, Natural Cycles is the first app certified as a form of contraception by the European Union. Natural Cycles uses a specially developed algorithm and other factors, including temperature, to determine which days a woman might be fertile. To get the certification the app had to follow the same path as other contraceptives as, for example, condoms and demonstrate in a series of clinical studies that it improves the effectiveness of traditional planning methods. Next, the company aims for certification in the U.S.