Sleep Cycle

AutoSleep

AutoSleep is a sleep-tracking app for Apple Watch and iPhone that records sleep automatically in the background, without requiring the user to start or stop a session. It uses heart rate, motion, and (where available) blood oxygen and wrist temperature data to estimate sleep stages, sleep quality, and a running sleep debt total called the sleep bank. The app integrates with Apple Health and HomeKit, offers a smart alarm that wakes users during a lighter sleep phase, and includes an add-on companion app, AutoSnore, for snore detection. It is sold as a single one-time purchase on the App Store rather than a subscription, and processes data on-device rather than through a cloud account.

Pillow

Pillow is a sleep tracking app for iPhone, iPad, and Apple Watch that automatically detects sleep cycles using motion and heart rate data, without requiring a separate wearable beyond an Apple Watch. It logs sleep duration and stages, then presents trend charts by week, month, and year alongside comparisons to steps, weight, and caffeine intake logged in Apple Health. A smart alarm wakes users during a lighter sleep stage within a chosen window instead of at a fixed hard time, and the app can record audio events like snoring or sleep talking overnight for playback. Pillow processes sleep analysis on-device and states that sleep data stays local to the user's devices rather than being uploaded to a server.

Rise Science

Rise Science (the RISE app) is a sleep and energy tracking app founded by Jeff Kahn and Leon Sasson, originally built to help athletes and sales teams improve performance through better sleep. Rather than just logging sleep, it calculates a personalized sleep-need number and tracks 'sleep debt' - the gap between the sleep you need and what you're actually getting. Using phone usage patterns and sleep-science algorithms, RISE predicts a user's daily energy cycle, telling them things like when their last coffee should be or when to wind down for bed, and nudges them with 16 science-based habits timed to their personal schedule. It integrates with Apple Health, Oura, and Fitbit, and is a subscription app with a 7-day free trial.

Renight

Renight, formerly known as Nightly, is a sleep optimization app from Munice Inc. that uses monaural beats, a brainwave entrainment technique, alongside AI-generated soundscapes and white noise. The app is aimed at people who have limited time in bed and want to get more restorative sleep out of fewer hours, backed by research collaborations including Yonsei University and the Korea Research Institute of Standards and Science. Beyond audio, Renight includes a sleep tracking calendar, snoring detection, morning activation sounds, and a sleep level system meant to build consistent habits over time. The company cites backing and recognition from Stanford Medicine, Google for Startups, and Samsung C-Lab, and the app has a 4.6-star rating across roughly 118 App Store reviews.