Primetide

Privacy policy

Last updated 28 September 2026

The short version

Who we are

Primetide is made by Jonathan Williams, based in the United Kingdom. For this policy we are the "controller" of your personal data under UK data protection law.

Contact: hello@primetide.app

What stays on your phone

The app keeps these on your phone only. They are not sent to us or synced anywhere:

Deleting the app deletes all of this.

Your location

The app asks for permission to use your location only while you are using it. It never tracks you in the background. It takes one reading of your position when you tap to use your location, and not otherwise.

That position is treated like any other place you look at: it is sent, rounded to about 10 metres, to the weather and tide providers below so they can return the forecast for it. Your phone's own location service (provided by Google on Android phones and by Apple on iPhones) may also be asked for the name of the place, so the app can show it.

You can say no to location permission and still use the app fully by searching for places by name instead.

What leaves your phone, and why

Primetide works by asking specialist data providers for forecasts and tide predictions. Each request carries only what that provider needs.

WhoWhat they receiveWhy
Open-Meteo (directly, or through our server)The position of the place you are looking at, rounded to about 10 metresWeather, wind, swell and sea temperature forecasts
WorldTides (through our server)The position of the place, rounded to about 10 metresTide times and heights
LocationIQ (through our server)The words you type into the place searchFinding places by name
NOAA, the US government's ocean agencyThe ID of the nearest US tide station and a date range. Your position is not sent: the app picks the station on your phone.Tide times and tidal flow predictions, for places in the US only
RevenueCat and your app storeAn anonymous customer number that RevenueCat creates, and your purchase detailsHandling Primetide Plus subscriptions and restoring them on a new phone

Like any internet service, these providers can see the internet (IP) address your request comes from, except where the request goes through our server, in which case they see our server's address instead of yours. Each provider handles data under its own privacy policy.

Our server

Some requests go through a small server we run on Cloudflare. It exists so that our keys for the data providers are never stored inside the app. With each request the app sends:

The server uses the install number only to stop any single copy of the app making an excessive number of requests. It does not log requests, store positions or searches, or keep install numbers. It does not pass your IP address or install number on to the data providers. Cloudflare, which runs the server's hardware, processes your IP address in order to deliver the connection.

The app also asks our server, when it starts, whether there is a notice to show, such as a message that an update is needed. That request carries only the app's version number.

Subscriptions

If you buy Primetide Plus, the payment is handled entirely by the app store you bought it from, such as Google Play or the Apple App Store. We never see your card details. RevenueCat, the service we use to manage subscriptions, receives the purchase details from the store and an anonymous customer number. We do not give RevenueCat your name, email or any other details about you.

Our legal basis

We use the data described here because it is needed to provide the app you have chosen to use (under UK GDPR, this is "performance of a contract"), and for keeping our server secure and our costs under control, which is in our legitimate interests. We use your location only when you ask the app to.

Where data goes

Some of the providers above are based outside the UK, including in the United States. Where data is transferred outside the UK, it is protected by the safeguards UK law requires, such as the UK's data adequacy arrangements or standard contractual clauses.

How long we keep it

Data kept on your phone stays until you delete it or remove the app. Our server keeps nothing after it has passed a request on. Providers keep data according to their own privacy policies.

Children

Primetide is not aimed at children under 13, and we do not knowingly collect data from them.

Your rights

You have the right to ask what personal data we hold about you, to have it corrected or deleted, to object to how we use it, and to complain. Because we keep no account or server records, we will usually hold nothing that can be linked to you. Email hello@primetide.app with any request and we will reply within one month.

You can also complain to the UK Information Commissioner's Office at ico.org.uk.

Changes to this policy

If we change how the app handles data, we will update this page and the date at the top before the change reaches the app.