# Hormetic — Honest heat & cold tracking > Honest thermal-dose tracker using heart rate and entered temperature. (iPhone/iPad app by Avesta Forge LLC.) - Source: https://appshunter.io/ios/app/hormetic/id6766344765 (this page in markdown: same URL + `.md`) - Developer: [Avesta Forge LLC](https://appshunter.io/developer/1164532185) - Category: Health & Fitness, Lifestyle - Price: $2.99 - Rating: 5.00/5 from 2 App Store ratings · 1 written reviews indexed - Age rating: 17+ - Requires: iOS 18.6 · 4 MB - Languages: American English - Released: 2026-06-09 - Data updated: 2026-09-06 - Monetization: paid - User reviews in markdown: https://appshunter.io/ios/app/hormetic/id6766344765/reviews.md ## What is Hormetic? Hormetic tracks how your body responds to heat and cold exposure, using heart rate and the temperature involved, with honest math and full transparency. WHAT YOU GET - Heart-rate tracking during a session, recorded as a standard HealthKit workout - Heat: three color-coded zones (Zone 1, Zone 2, Zone 3) and an estimated heat-dose score from your heart rate, the temperature you enter, and session duration - Cold: cold-plunge tracking with three calm zones — Entering, Moderate, Significant — and an estimated cold dose from your time in the water and the water temperature - Spa (new): hot tubs and hot baths, with their own zones and an estimated soak dose from your time immersed and the water temperature. A separate algorithm from heat — a 40 °C soak is not a 90 °C sauna, and one score cannot honestly describe both - Contrast: follow a sauna or a soak with a plunge and Hormetic notes the pattern with honest, recovery-framed context — never a combined-benefit claim - Per-session detail: peak heart rate, time in each zone, calories, algorithm version - Adapt: your weekly consistency, with estimated heat, cold, and soak dose as separate trends - Full session history HONEST BY DESIGN - Every value the algorithm derives is labeled "Estimated" - Heat, cold, and spa use separate, independently versioned algorithms; each session records the version that produced its values - In cold and spa, heart rate is shown for context but never scored — water changes it in ways a wrist reading can't fairly judge - The soak estimate stops growing past 40 °C and past 20 minutes, because that is where the published evidence stops. More time is not more dose - Historical sessions are never silently recomputed - Grounded in published research, with tappable source citations; water safety and its risks are covered prominently in the app PRIVATE BY ARCHITECTURE Your data never leaves your device. No account. No analytics. No telemetry. No third-party SDKs. We do not sell personal information. IMPORTANT — YOUR DEVICES Hormetic never asks you to put a device anywhere Apple's own guidelines say it should not go. For heat, Hormetic does not require you to place your Apple Watch or iPhone in any hot room — the temperature is a value you enter manually, and Apple Watch simply contributes heart rate from your wrist. Cold plunges, hot tubs, and hot baths are shallow-water immersion, which Apple Watch's water resistance supports. Hormetic's own in-app guidance caps a soak at 40 °C (104 °F), well under the 55 °C (130 °F) figure Apple publishes for Apple Watch Ultra in a hot environment. As Apple recommends, rinse your Watch with fresh water after a treated pool or tub. On Apple Watch Ultra, submersion and water temperature are read by the watch's built-in sensor; on other models you enter the water temperature. Keep your devices within Apple's published guidelines — water resistance is not permanent, and depth limits apply. IMPORTANT — YOUR HEALTH Cold-water immersion carries real risk. The cold-shock response can cause gasping and raise heart rate and blood pressure — enter gradually, never breath-hold beforehand, and don't plunge alone. Hot water is a real cardiovascular load. Stand up slowly, hydrate, skip alcohol, and don't soak alone. Get out at the first sign of dizziness, nausea, or headache. Hormetic is not a medical device and does not diagnose, treat, or prevent any condition. Consult a healthcare professional before starting heat or cold exposure, especially with a heart condition, high blood pressure, or pregnancy. REQUIREMENTS iPhone running iOS 18 or later. Apple Watch optional, used for heart rate; Apple Watch Ultra adds automatic submersion detection and water-temperature sensing for cold plunges and soaks. ## Key features - Heart-rate tracking during sessions - Three-zone classification with color-coded badges - Estimated heat-dose score calculation - Per-session detail and full history - Algorithm versioning for transparency - Private data architecture, no account needed ## Recent user reviews (1 of 1) All indexed reviews: https://appshunter.io/ios/app/hormetic/id6766344765/reviews.md ### 5/5 — Super Useful and No More Guesswork *2026-06-09* I really like this app because I no longer have to guess how long I need to sit in the sauna. I always knew that the time I want to be in the sauna varies based on my location and being in Texas vs Alaska, I can finally dial that in without having to guess all the time. ## Frequently asked questions about Hormetic ### What is Hormetic? Hormetic is a health and fitness app that tracks your body's response to heat exposure. It uses your heart rate and a temperature you manually enter to estimate a heat-dose score and provide detailed session insights. ### How does Hormetic track heat exposure? Hormetic uses your heart rate, the temperature you manually input, and the session duration to calculate an estimated heat-dose score. It also records your heart rate as a HealthKit workout. ### Is Hormetic private? Yes, Hormetic is designed for privacy. Your data never leaves your device, and there is no account, analytics, or telemetry. It does not sell personal information. ### What devices does Hormetic support? Hormetic requires an iPhone running iOS 18 or later. An Apple Watch is optional and is used for heart rate tracking. ### How much does Hormetic cost? Hormetic is a paid app, available for $1.99. It does not have in-app purchases or advertisements. ### Does Hormetic have ads? No, Hormetic is ad-free. As a paid application, it does not contain any advertisements. ### How often is Hormetic updated? The latest version of Hormetic is 1.4, last updated on June 28, 2026. The app's algorithm is versioned independently from the app itself for transparency. ### What is the age rating for Hormetic? Hormetic has an age rating of 17+. This is likely due to the nature of health tracking and the recommendation to consult a healthcare professional before starting new activities. ## Version history (last 5 releases) ### 1.6.5 — 2026-08-24 Learn covers all three, not just heat The Learn tab now carries cold and hot-water sections alongside the sauna research, each with its own reference list. New explainer: the three stages of cold-water immersion — cold shock, physical incapacitation, then hypothermia. Safety knowledge, not technique. No stage is something to chase, and the app says so. Your session, with the studies attached Cold and hot-water sessions now get the tailored, cited explainers heat has had: what this particular session was, and what the research actually says about it. Plunge after a sauna and you will see the contrast evidence — including its honest gap, since those studies alternated hot water with cold rather than dry heat. A clearer read on consistency Adapt now charts sessions per week against Hormetic's consistency threshold, instead of shading days by minutes logged. Press and hold any weekly dose chart to scrub across it and read the actual numbers, week by week. Delete a session Swipe left on any row in the Log. Useful for the accidental starts that used to be stuck there for good. Accidental sessions no longer count anywhere Tap Start and stop within a few seconds and nothing is recorded — not in Hormetic, and not in Apple Health. Previously a stray tap left a 0:00 workout in Health that Hormetic hid but could not remove. Fixes A hot-tub session followed by a cold plunge was described as a heat session. It now names the soak correctly — hot water and dry heat are kept on separate books everywhere else in the app, and this was the one place that slipped. Every model-derived value is still labeled Estimated, every claim still links to its source, and nothing leaves your device. ### 1.6.0 — 2026-08-04 SPA MODE — hot tubs and hot baths Step into the water and your Apple Watch Ultra starts the session on its own, reading the water temperature from its built-in sensor. Other models: start it by hand and enter the temperature. • Its own zones and its own estimated soak dose — a separate algorithm from sauna, because a 40 °C soak is not a 90 °C room, and pretending one score fits both would be dishonest • The clock keeps running when you rest an arm on the rim: the rest of you is still in the water. Your Watch taps once and says so on screen • Time immersed is time immersed — the walk to the tub and the towel-off afterward are not counted • Hot-water safety built in: the recommended ceiling, why to stand up slowly, and who should ask a doctor first • Sauna and cold plunge estimates are unchanged ### 1.5.1 — 2026-07-25 • Cold plunges without a water temperature no longer reach the top zone on time alone — without a reading, there isn't enough to estimate real cold stress. • Sessions over an hour now display correctly on iPhone. • Steadier Watch sessions: sauna and cold now share one session core, so starts, finishes, and Finish & Switch are more reliable. • Estimated sauna scores are unchanged. ### 1.5.0 — 2026-07-21 Cold plunges, tracked as honestly as your sauna. Hormetic now tracks cold-water immersion alongside heat. Choose Cold on your Apple Watch and it logs your time in the water and an estimated cold dose across three calm zones — Entering, Moderate, Significant. On Apple Watch Ultra it senses when you're submerged and reads the water temperature for you; on other watches, you enter it. Also new: • Cold-water safety, taken seriously — cold immersion carries real risk, and the app covers it with cited sources. • Contrast, explained — follow a sauna with a plunge and Hormetic notes it, with honest, recovery-framed research (never a combined-benefit promise). • Cold trends in Adapt — your weekly cold dose, kept separate from heat. • In cold, heart rate is shown but never scored — cold changes it in ways a wrist reading can't fairly judge. As always, every zone and dose figure is an on-device Estimate. No account, no tracking — nothing leaves your phone. ### 1.4 — 2026-06-28 Steam and infrared sessions now get their own heat-dose estimate. Pick your heat type on a redesigned start screen with bigger, easier-to-tap buttons, and the temperature sets a sensible default for that type (handy in a steam room, where there's rarely a gauge). Also new: • Heat type on every session — your dry / infrared / steam choice now shows on the session screen. • "Before your session" context — see the workout you did beforehand, with honest, research-based framing (never a promise). • A quick "your (10th) heat session this week." • Refreshed science — updated citations and clearer wording: heat adaptations build with how often you go, not any single session. As always, every value is an on-device Estimate. No account, no tracking — nothing leaves your phone. ## More apps by Avesta Forge LLC - [Gymnasticky](https://appshunter.io/ios/app/gymnasticky/id1164532186) - [Holiday Stickit - Holiday Stickers](https://appshunter.io/ios/app/holiday-stickit-holiday-stickers/id1169296153) - [Anygoline VPN](https://appshunter.io/ios/app/anygoline-vpn/id6783892973) - [Sectional AI](https://appshunter.io/ios/app/sectional-ai/id6790005512) All apps by Avesta Forge LLC: https://appshunter.io/developer/1164532185 --- *Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-09-06.*