Contrast is a timer and a record for sauna, hot bath and cold plunge. It is not a medical device and does not diagnose, treat, cure, or prevent any medical condition, and it does not give medical advice. Every figure in the Analysis tab is a statistic computed from your own sessions and your own Apple Health data, not a clinical measurement; a comparison describes what goes together, not what causes what, and no result is predicted or promised. Talk to a doctor before starting sauna or cold exposure, especially if you have a heart condition, high or low blood pressure, or are pregnant.
Sauna and cold plunge, timed from the water.
Contrast is an app by Fluctus Limited. © 2026 Fluctus Limited.