Last updated 9 September 2026
I'm Tom, and I built PowDay. This is the entire policy. It's short because there genuinely isn't much to say.
There are no accounts, so there's nothing to sign up for and nothing to sign in to. There's no analytics SDK, no advertising identifier and no crash reporter, because the app has no third-party code in it at all. I don't know who you are, which mountains you picked, or whether you opened the app this morning.
Your mountains, their order, your snow threshold and your alert time are stored on your iPhone and stay there. Deleting the app deletes them.
PowDay reads public data straight from the agencies that publish it. Those servers see your device's IP address and the fact that something asked for a snow report, the same way any website does when you visit it. I never see those requests.
api.weather.govNational Weather Service forecastswcc.sc.egov.usda.govUSDA SNOTEL snow telemetrywsdot.wa.govWSDOT mountain pass reports and highway alertsapi.avalanche.orgNWAC avalanche danger, via the National Avalanche CenterThe app asks my own server one question when it launches: is any feature switched off? That request is anonymous and carries nothing about you. Cloudflare runs that server and keeps ordinary web logs; I've built nothing on top of them, and nothing that could tie a request to a person.
The trail map is drawn on Apple Maps, so Apple's servers see which map tiles your phone asks for, under Apple's privacy policy. If you tap the locate button on that map, iOS shows your position on it for you. PowDay reads your location only while you record a day or tap that button, stores a recorded day on your iPhone, and never sends it anywhere. The one copy that can leave the app is the optional Apple Health workout described below, which you switch on yourself and which carries no track.
From version 1.1: if you tap Record, PowDay reads your GPS position and the phone's barometer while you ride, and works out your runs, lifts, vertical and speed on the phone. The track and the numbers are saved in the app's own container on your iPhone. PowDay never sends it anywhere: there is no PowDay server that could receive it, and the code that records has no way to reach the network. Your own iPhone backup (iCloud or a Mac) includes the app's data the way it does for every app, under Apple's terms. The track and its GPS fixes never leave the app any other way. Delete the app and every recorded day goes with it.
While a recording runs, iOS shows a blue indicator at the top of the screen. That is iOS telling you PowDay is using your location in the background, which it needs to do so your day keeps recording with the phone in your pocket. Pause the recording and the indicator goes away. PowDay asks for location "while using the app" only; it never asks for "always".
TestFlight builds carry one extra door on a recorded day's screen: "Export this day", which writes that day to a file and hands it to the iOS share sheet. You choose where it goes — to the developer, to yourself, or nowhere. Nothing is exported by itself, and the App Store build has no such door.
From version 1.2: if you record on an Apple Watch, the watch reads your heart rate while the day is recording, so the day can show it. Those readings are stored with that day on the watch and on your iPhone, and go nowhere else: the watch sends the finished day straight to your iPhone over Apple's device-to-device link, with no server in between. Nothing else is read from Health, and the iPhone app itself reads nothing at all. The first time you record on the watch it asks for permission to save the day to Apple Health and to read your heart rate; if you decline the heart-rate part, the day still records and simply has no heart rate in it.
If you switch on Save days to Apple Health in Settings (it is off until you do), each finished day is written to Apple Health as a workout: its start and end, distance and vertical, and nothing else. The track itself is not written. What is stored there is covered by Apple's Health privacy terms.
Tapping Directions hands the mountain's coordinates to Apple Maps, and PowDay steps out of the way. Tapping Lifts, Cams, Parking, Official trail map or Lift status opens that resort's own website, where their privacy policy applies instead of mine.
Storm alerts are worked out on your phone. iOS wakes PowDay in the background, it reads the NWS forecast, and if one of your mountains is over your threshold it schedules a local notification. Your threshold never leaves the device, and there's no push server involved.
From version 1.2: pass alerts work the same way. When you open PowDay, and when iOS wakes it in the background, it reads WSDOT's pass report and highway alerts for your mountains, compares them with the last ones it saw on your phone, and schedules a local notification if a chain requirement, a travel advisory or a closure changed. Nothing is sent anywhere, and there's no push server involved.
Pro is a one-time $4.99 purchase, handled start to finish by Apple's In-App Purchase system. Apple takes the payment and tells the app exactly one thing: whether this Apple ID has bought it. I never see your name, your email or your card. Apple's privacy policy covers that transaction.
PowDay isn't directed at children, and since it collects nothing from anyone, there's nothing about a child to collect either.
I'll edit this page and the date at the top. Because the app collects nothing, I have no way to email you about it, which is the tradeoff: worth a look if you care.
Ask me: tomnguyentpm@gmail.com
PowDay is not affiliated with Crystal Mountain, Stevens Pass, The Summit at Snoqualmie or Mt. Baker.