Frost is the only Raynaud's app on iOS. Set your cold threshold and get warned before temperatures drop, log episodes by finger or toe, and see exactly what triggers your attacks.
A sudden temperature drop sets off an episode before you've even reached for gloves. Frost warns you first.
"My fingers go white sometimes" isn't much to go on. Frost turns your episodes into clear, shareable evidence.
No account. Your data lives on your device and your own private iCloud - never on our servers.
Log severity 1-5 and tap the exact fingers or toes affected, plus colour changes and how long rewarming took.
Set your personal vasospasm threshold and Frost warns you before the temperature drops - so you can layer up in time.
Frost captures the temperature, wind and humidity at the moment of each episode, so the context is always recorded.
See how cold, stress, caffeine and hormones correlate with your attacks - with confidence ratings, not guesses.
Plain-language articles on Raynaud's, triggers and day-to-day management, right inside the app.
Export a one-page report - episode frequency, severity, triggers and weather - for your rheumatologist.
Frost has no account and no servers of ours. Episodes live on your device and, if you enable it, sync through your own private iCloud. To check the weather and send alerts, only your approximate location is sent to OpenWeather.
No analytics, no ads, no tracking.
Sync happens in your Apple account, not ours.
Just your location goes out, for forecasts.
Yes - episode logging, the body map, automatic weather capture and cold-weather alerts are free. Premium ($7.99/month or $49.99/year) adds full insights, unlimited history, the complete tips engine and the doctor PDF, with a 1-month free trial.
You set a personal temperature threshold. Frost checks the forecast and sends a local notification before conditions drop below it. Alerts depend on weather data and your settings, so treat them as a helpful heads-up, not a guarantee.
If you're signed into iCloud, Frost syncs through your own private iCloud (CloudKit). We have no access to it and run no servers that store your data.
No. Frost is a personal tracking tool, not a medical device. It helps you record episodes and patterns to discuss with your doctor.
An iPhone on iOS 17 or later.
Let Frost track your episodes and warn you before the temperature turns against you.