Finally getting it right
got a cold plunge and had no idea what i was doing with the water. this tells me straight up what to add. way less murky now
Free
In-App Purchases
About
This app helps maintain cold plunge water chemistry by calculating precise sanitizer and pH doses based on your tub's volume. It offers safety warnings for chemical interactions and provides guidance on water changes and filter maintenance.
✓Dual-path sanitizer math (chlorine/peroxide)
✓Drain-required safety interlock
✓Water-change cadence tracking
✓Cloudy-water diagnostic
✓After-session top-up doses
✓Filter maintenance tracking
✓Metric/imperial unit support
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What's New in Frost
1.3
August 26, 2026
Maintenance update. No feature changes.
1
In-App Purchases
$4.99
Frost Pro (lifetime)
Dosing, top-ups, cadence & cloudy-water diagnostic
User reviews
Developer apps
FAQ
What is Frost used for?
Frost is an iOS water-chemistry assistant designed specifically for cold plungers. It helps you calculate exact doses of sanitizers and pH adjusters based on your plunge's volume, ensuring optimal water quality and safety.
How does Frost handle different sanitizers?
Frost supports dual-path sanitizer math for both chlorine (Dichlor, Cal-hypo, liquid) and hydrogen peroxide (household, food-grade). It also includes a crucial drain-required safety interlock to prevent dangerous chemical neutralization when switching between chlorine and peroxide.
Does Frost have a subscription or ads?
No, Frost operates on a one-time purchase model. It explicitly states 'No subscription, no ads, no account, no cloud,' meaning all functionality is available offline and without ongoing costs or advertisements.
What is the price of Frost?
Frost is available for a one-time purchase of $3.99. This single payment grants you full access to all its features without any recurring subscription fees or in-app purchases.
What devices does Frost support?
Frost is a universal app designed for both iPhone and iPad. This means you can use it seamlessly on any of your Apple mobile devices.
How often is Frost updated?
The latest version of Frost is 1.3, which was last updated on August 26, 2026. While specific update frequency isn't detailed, this indicates recent development and support.
Is Frost suitable for all cold plunge setups?
Frost is optimized for home setups ranging from 80–120 gallons (300–450 L). This includes chiller-based systems, DIY chest-freezer builds, and any setup within that volume range.
Does Frost collect user data?
No, Frost prioritizes user privacy by collecting absolutely nothing. It has no analytics, no accounts, and no network requests, ensuring all your settings and data remain securely on your device.
