SAUNA + COLD PLUNGE

Contrast therapy,
timed.

A purpose-built timer for sauna and cold plunge sessions. HealthKit sync, smart protocols, Apple Watch support.

Download on the App Store Free · No account required
Contrast app icon
Contrast home screen Active sauna timer Active cold plunge timer Multi-phase protocol Session complete Personal records Session history
FEATURES

Built for the session.

Quick Start

Two taps to start timing. Sauna or cold plunge — pick one and go. Designed for wet hands and foggy glasses.

Smart Protocols

Multi-phase session plans that guide you through sauna, cold plunge, and rest intervals with automatic transitions.

HealthKit Sync

Sessions save to Apple Health as workouts automatically. Your contrast therapy shows up alongside everything else you track.

Session History

Every session is saved. Track personal records, total exposure time, and build the consistency that drives results.

Apple Watch

Start, pause, and advance phases from your wrist. Haptic alerts tell you when it's time to switch — no phone needed.

Completely Offline

No servers, no cloud sync, no network requests. Your data stays on your device. Period.

PRIVACY

Zero data collection.

No analytics. No ads. No tracking pixels. No telemetry.
Contrast doesn't even make network requests. Your session data lives on your device and nowhere else.

Read the full privacy policy →

Start your session.

Free on the App Store. No account required.

Download on the App Store

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