Sauna Flow: Sauna Timer & Log

Time your sauna sessions from your wrist and see your heart rate zone as you go. Sauna Flow is a sauna timer for Apple Watch that keeps a clear record of every session on your iPhone.

Set a target time, start on your Apple Watch, and stay focused on the heat. Afterwards, your iPhone shows how the session went and how your routine is building week by week.

■ Round mode
• Plan 1 to 5 rounds of sauna, cool-down and rest on your Apple Watch.
• Each sauna phase starts when you tap. Cool-down and rest move on automatically, with a haptic at each change.
• Your iPhone shows a breakdown for every round.

■ Live heart rate on your Apple Watch
• See your current heart rate and zone during the session, with optional alerts when your zone changes.
• Zones are based on a max heart rate you choose: the default, an age-based estimate, or your own value.

■ Your sauna routine
• A session calendar that marks the days you went.
• Current and longest streak, plus a weekly goal you set (1 to 14 sessions).
• Optional reminders on the weekdays and at the time you pick. They stay off unless you turn them on.
• Session details: duration, average and highest heart rate, time in each zone, plus effort and stability scores for single sessions.
• Export your sessions to CSV or share a session card.

■ On your watch face
• Add the Sauna Flow complication to open the app in one tap.

■ Sessions you can count on
• Each session stays on your Apple Watch until your iPhone confirms it is saved, and is resent automatically.
• If the app closes mid-session, the session is recovered and saved as interrupted.
• If your Apple Watch gets too hot, it warns you. If it overheats, the session is saved and ended.

■ Apple Health
• Sessions and heart rate data are saved to Apple Health.

■ Your language
• Korean, English, German, Finnish, Japanese, Dutch and Russian. Choose in the app's settings; your Apple Watch follows.

■ Premium
• Your 3 most recent sessions are always available. Sauna Flow Premium, an in-app purchase, unlocks your full session history and full export.

■ What you need
• Apple Watch with watchOS 10 or later to record sessions.

■ Please note
• Sauna Flow is not a medical device and does not provide medical advice. Heart rate zones are informational estimates, not medical measurements.
• If you have a cardiovascular condition or other health concerns, consult your doctor before using a sauna.
• Stay hydrated and avoid overheating. Stop your session immediately if you feel unwell.
• Apple Watch and iPhone are not designed for extreme heat. Do not expose your device to sauna temperatures beyond its operating range (Apple Watch: 0–35°C / 32–95°F); keep it somewhere safe. Protecting your device is your responsibility.