Natural Cycles is a birth control app backed by science, using an FDA cleared algorithm powered by body temperature to track fertility and help with pregnancy planning.

Users can use a free thermometer or sync devices like Apple Watch or Oura Ring to measure body temperature upon waking. The app then uses this data to show fertility status, cycle trends, and provides customized insights. It aims to offer a personalized, hormone-free birth control option that maintains user data privacy.

The app has a typical use effectiveness rate of 93% and perfect use effectiveness of 98%, supported by clinical evidence. Natural Cycles charges a subscription which supports accessibility to hormone-free birth control and women's health research, while ensuring data privacy compliance as a regulated medical device.