The short answer
If you want the app most people have rated, it is HotLog: 4.6 stars from 530 ratings on the US store, $1.99 once, but no Apple Watch app, so it logs sessions rather than timing them on the wrist. If you want the watch itself to run the session, the most rated choice is GoPolar (4.7, 315 ratings, free, built around cold plunges and also for Garmin), then Sauna Tracker: Sleep & Plunge (4.3, 26 ratings, $5.99 up front). Sauna Metrics is ours: choose it for rounds and breaks timed separately on the watch, a heart rate alert, a 10-minute recovery countdown and six Health analyses, and know its limits before you do: it was released in May 2026, shows 1 rating on the US store (8 across all its storefronts on 4 November 2026), requires iOS 26, and its watch app is part of a subscription with no lifetime purchase. If you refuse subscriptions, Sauna Tracker, Sauna Log, Sauna Assistant, HotLog and Sauner are paid once, and SUNA and Contrast offer a lifetime option.
How we compared
Every figure on this page comes from the public US App Store listing of each app through Apple's lookup API: price, rating, number of ratings, version and date of the last update, supported devices and the listing's own text, read on 5 November 2026. "Apple Watch app" means Apple Watch is among the supported devices of the listing. What each app does is what its listing says: we did not install and score all twelve, so a feature a listing does not mention may still exist. Ratings move every week; the links go to each listing so you can check today's numbers. Sauna Metrics is our app, and where a competitor is cheaper or does something it does not, this page says so.
The apps at a glance
| App | Apple Watch app | Rounds & breaks | Heart rate alert | Saves to Apple Health | Price | Rating (US) | Last update |
|---|---|---|---|---|---|---|---|
| Sauna Metrics: Tracker & LogPhilippe Barradas | Yes | Yes | Yes | Yes | FreePro: monthly or yearly subscription, free week on the yearly plan | 4.0 (1) | 28 Oct 2026 |
| Sauna Tracker: Sleep & PlungeFrank Vincent Petruccelli | Yes | No | Yes | Yes | $5.99Paid up front | 4.3 (26) | 4 Nov 2026 |
| HotLog - Sauna & Cold PlungeThomas Dori | No | No | No | Yes | $1.99Paid up front; the listing mentions no subscription | 4.6 (530) | 22 Sep 2026 |
| GoPolar: Cold Plunge & SaunaThe Wellness Company, Inc. | Yes | No | No | No | FreeThe listing does not say what is paid | 4.7 (315) | 22 Oct 2026 |
| SUNA - Sauna TrackerJan Kriz | Yes | Yes | No | No | FreeSuna+: monthly, yearly or lifetime | 1.0 (2) | 15 Oct 2026 |
| Sauner - Sauna Tracker & LogStackWorks LLC | Yes | Yes | Yes | No | $0.99Paid up front; the listing mentions no subscription | 4.3 (9) | 2 Feb 2026 |
| Sauna LogBarnaby Wood | Yes | No | Yes | No | Free3 sessions free, then one purchase, no subscription | no ratings yet | 28 Oct 2026 |
| Sauna Assistant: Ritual TimerDainius Serplis | Yes | Yes | No | Yes | $19.99Paid up front, no subscription, no in-app purchases | no ratings yet | 19 Oct 2026 |
| Contrast: Sauna & Plunge LogFluctus Limited | Yes | Yes | No | Yes | FreeContrast Pro: yearly, monthly or lifetime | no ratings yet | 13 Oct 2026 |
| Sauna Flow: Sauna Timer & LogAndroa Inc. | Yes | Yes | Yes | Yes | FreePremium in-app purchase for the full history and export | no ratings yet | 13 Oct 2026 |
| Max SaunaNaoki Anraku | Yes | Yes | No | Yes | FreeEvery feature free, no ads, says the listing | no ratings yet | 3 Nov 2026 |
| SaavuRivoro Studio | Yes | Yes | No | No | FreeSaavu Pro for the full history and analytics | no ratings yet | 27 Oct 2026 |
Ratings are the US storefront's, to one decimal, with the number of ratings in brackets. A dash means the listing does not mention the feature. A free app may sell a subscription or a purchase inside; the price column says what the listing says about it.
Sauna Metrics: Tracker & Log
Free to download, with a Pro subscription (monthly, or yearly with the first week free) for the Apple Watch app, the widgets and the Health analyses. On the watch: each round and break timed on its own, live heart rate, a tap when your heart rate passes your limit, water lock, and a 10-minute heart rate recovery countdown when you step out. On iPhone: a round-by-round timer with a Live Activity, a log with temperature, humidity, sauna type (Finnish, infrared, steam), water, mood, stress, notes and a photo, a score out of 100, sweat and electrolyte estimates, heat age, streaks and badges, Siri and a Control Center button. Sessions are saved to Apple Health as Preparation and Recovery workouts and exported as JSON. Twenty-three languages in the app, 20 on its App Store listing. What it lacks against the others: no cold plunge timer (a cold plunge is only a tick on the sauna session), no Garmin, no CSV, no lifetime purchase, iOS 26 required, and very few ratings yet. Read How to track a sauna session on Apple Watch and Sauna timer and log app for iPhone.
Sauna Tracker: Sleep & Plunge
$5.99 up front, iPhone and Apple Watch, English only. Its listing claims over 250,000 sessions tracked and covers sauna, cold plunge, hyperbaric oxygen and red light sessions, with live heart rate on the watch, heart rate alerts, "benefit zones" during the session, a sleep and recovery dashboard computed from Apple Health, traditional, infrared and steam sauna types, and workouts and heart rate written back to Apple Health. It is the most rated sauna-first watch app on the US store, first released in January 2025 and at version 1.23 on 4 November 2026. Choose it over Sauna Metrics if you want one paid app, with no subscription mentioned on its listing, that also times cold plunges; the listing does not mention rounds and breaks timed separately.
HotLog - Sauna & Cold Plunge
$1.99 once, on the store since 2018, English and German, 4.6 stars from 530 ratings: the best-rated sauna log by a wide margin. The listing describes a log of sauna, steam bath, infrared and cold plunge sessions with type, temperature, humidity, duration, Aufguss and cold plunges, statistics and trends, and sessions saved as workouts to Apple Health. Its listing lists no Apple Watch app, so there is no timer or heart rate on the wrist. Choose it if you log sessions after the fact and want the cheapest proven app; choose a watch app if you want the session timed and measured as it happens.
GoPolar: Cold Plunge & Sauna
Free, 4.7 stars from 315 ratings, Apple Watch and Garmin. Its listing is about cold plunges first: ice baths, cold showers, sauna, red light and hyperbaric sessions, with duration, temperature, heart rate and blood oxygen, a community, challenges and badges. The listing does not say what, if anything, is paid. Choose it if cold is your main practice and you want a community; the sauna is one session type among five.
SUNA - Sauna Tracker
Free with Suna+ (monthly, yearly or lifetime) for the full history, Apple Watch, five languages. The listing describes a ritual of three phases (heat, cooling, rest) started from the watch with optional haptics, a Sauna Score, heart rate when the watch is worn, notes, plans and reminders. It shows 1 star from 2 ratings on the US store, too few to mean much either way. Choose it for a phone-free three-phase ritual with a lifetime option.
Sauner - Sauna Tracker & Log
$0.99 once, Apple Watch, five languages including Finnish, Japanese and Korean. The listing describes unlimited rounds with heat, cold water and rest phases timed separately, live heart rate on the watch with a target alert, a "Totonoi" score and statistics. 4.3 stars from 9 ratings; last updated in February 2026, the oldest update in this list. Choose it as the cheapest paid watch app with rounds, if a slow update pace does not bother you.
Sauna Log
Free for 3 sessions, then one purchase, no subscription. Apple Watch and Garmin (through the Connect IQ companion), eight languages. The listing describes timer presets started from the watch, sauna or steam room, live heart rate and calories, temperature and humidity, a cold shower tick, and progress across weeks, months and years. No ratings yet on the US store. Choose it if you own a Garmin, or want a watch timer paid once.
Sauna Assistant: Ritual Timer
$19.99 once, no subscription, no in-app purchases: the most expensive here. The listing describes guided rituals with audio cues played through the sauna's speakers (the iPhone stays outside), custom rounds and plunges, Live Activities, widgets, Siri, Apple Watch control, 17 soundscapes, Apple Home and Saunum heater control, and sessions saved to Apple Health as Mindful Minutes. With Apple Watch it shows live heart rate and zones. Choose it for a guided home sauna ritual with sound, paid once.
Contrast, Sauna Flow, Max Sauna and Saavu
Four newer watch apps, none rated yet on the US store. Contrast (free, Pro by subscription or lifetime) times sauna, hot bath and cold plunge rounds; on an Apple Watch with a water temperature sensor, getting into water starts a round by itself, and every session is saved to Health as a Cooldown workout. Sauna Flow (free, Premium purchase for the full history) plans 1 to 5 rounds on the watch with heart rate zones, exports to CSV and saves to Health. Max Sauna (free, every feature free) scores the afterglow by heart rate recovery at 1, 3 and 5 minutes, exports PDF and CSV and saves to Health; Apple Watch is required to record a session, and its first version is from November 2026. Saavu (free, Pro for the full history) reads the watch's heart rate through HealthKit and adds venue check-ins. Contrast's automatic water rounds, and the CSV of Sauna Flow and Max Sauna, are things Sauna Metrics does not do.
Which one, by what you want
- The most rated: HotLog on iPhone; GoPolar among watch apps.
- Cheapest with an Apple Watch app: Max Sauna (every feature free) and Contrast (all watch tracking free); among paid apps, Sauner, $0.99 once.
- Paid once, no subscription: Sauna Tracker, HotLog, Sauner, Sauna Log, Sauna Assistant; SUNA and Contrast sell a lifetime option. Sauna Metrics has none.
- Garmin: GoPolar and Sauna Log.
- Cold plunge as a timed activity: GoPolar, Sauna Tracker, Sauner, Contrast, Sauna Assistant; HotLog as a log. Sauna Metrics notes it on the session.
- Rounds and breaks timed separately on the watch: Sauna Metrics, Sauner, Sauna Flow, SUNA (three phases), Contrast, Max Sauna.
- Heart rate alert on the watch: Sauna Metrics, Sauna Tracker, Sauner, Sauna Log (thresholds), Sauna Flow (zone changes).
- Heart rate recovery after the session: Sauna Metrics (10-minute countdown on the watch, a Pro analysis on iPhone), Max Sauna (1, 3 and 5 minutes).
- Export: CSV in Sauna Flow and Max Sauna (PDF too); JSON in Sauna Metrics.
- Infrared as a sauna type: Sauna Metrics, Sauna Tracker, HotLog, Max Sauna.
- Most languages on the listing, among these twelve: Sauna Metrics (20), Sauna Log (8), Sauna Flow (7).
Apple Watch, heat and Apple Health
Whatever the app, Apple rates the watch for ambient temperatures up to 35 °C (55 °C for Ultra), and Apple Health has no sauna activity: every app picks the closest workout type (Preparation and Recovery, Cooldown, Mindful Minutes). How to track a sauna session on Apple Watch explains what that means for your data, and Staying safe what to watch for in the heat.
Questions
What is the best sauna app for Apple Watch?
There is no single answer. On 5 November 2026, HotLog had the most ratings (4.6 from 530) but no Apple Watch app; GoPolar was the most rated app with a watch app (4.7, 315) and is built around cold plunges; Sauna Tracker: Sleep & Plunge was the most rated sauna-first watch app (4.3, 26, $5.99). Sauna Metrics times rounds and breaks on the wrist with a heart rate alert and a recovery countdown, but is newer, has few ratings, needs iOS 26 and puts the watch app in a subscription.
Which sauna apps have no subscription?
Sauna Tracker ($5.99), HotLog ($1.99), Sauner ($0.99), Sauna Log (one purchase after 3 free sessions) and Sauna Assistant ($19.99) are paid once, according to their listings. SUNA and Contrast sell a lifetime option next to a subscription. Sauna Metrics Pro is a monthly or yearly subscription with no lifetime purchase.
Does Apple Watch have a sauna workout?
No. The Workout app has no sauna activity, and Apple Health has no sauna type either, so sauna apps save sessions as the closest workout: Preparation and Recovery for Sauna Metrics, Cooldown for Contrast, Mindful Minutes for Sauna Assistant.
Which sauna apps work with a Garmin watch?
GoPolar and Sauna Log list Garmin support; Sauna Log needs its free Connect IQ companion. Sauna Metrics is for Apple Watch only.
Where do these numbers come from?
From the public US App Store listing of each app, read through Apple's lookup API on 5 November 2026: price, rating, number of ratings, last update and supported devices. The links in the table open each listing, where today's numbers may differ.
