Sleep Calculator: Cycle Sound is a utility application designed for iPhone users to enhance their sleeping habits. The app features a Sleep Cycle Calculator that helps users determine the optimal time to sleep based on their desired wake-up time, focusing on the 90-minute sleep cycle. Additionally, it includes a Sleep Duration Calculator, allowing users to find the best bedtime and wake-up time according to their preferred sleep duration.

Moreover, the app offers a selection of soothing sleep sounds aimed at helping users fall asleep faster and achieve a more restful sleep. A subscription package provides unlimited access to all features, with options for auto-renewal and management through the user's account settings. The user-friendly interface ensures easy navigation and accessibility for all users.