Sauna set timer and log with heart rate and on-device AI reflection.

Features

• Set timer for sauna, cold plunge, and rest phases, with Lock Screen and Dynamic Island Live Activity and a notification when each phase ends.
• Session log with durations, temperature, condition rating, and facility notes, synced through iCloud.
• Heart rate from Apple Health shown per phase, with an optional heart rate limit that requests a notification when reached (checked only while a set timer is running and the app is open; iOS may not show notifications while the app is in the foreground).
• Widget and Siri shortcut to start a set quickly.
• On-device AI reflection and monthly trend charts (Full Access).
• Humidity, sauna type, and aufguss count can be added to each session; when you add a session manually, the facility name, sauna type, and set times, temperatures, and humidity start from your previous entry (aufguss count does not carry over).
• Finished sessions can be saved to Apple Health as workouts, and the session's active energy can be shown on the detail screen (both can be turned off in Settings on iPhone; the Apple Watch app records its own workout in Apple Health, which this setting does not control).
• Challenges and achievement badges, plus a tips guide for sauna basics and safety.
• Siri and Shortcuts action to add a session to your log.
• Apple Watch app.