Privacy policy
Last updated: 9 November 2026
Choo Choo shows live UK train departures for the trips you save. It is made by Joao Martins as a personal project. This policy covers the Choo Choo apps for iPhone, Apple Watch and Mac, the Choo Choo server at choochoo.stream, and the Choo Choo connector for Claude.
Who is responsible for your data: Joao Martins, contact nomukaiki+choochoo@gmail.com.
What stays on your device
- Your location. If you allow it, Choo Choo uses your location to find your nearest station and to put the most relevant trip first. This happens on your iPhone or Mac. Your location is never sent to us or anyone else.
- Your settings. Server, location and network choices, widgets and the watch complication are stored on each device and never leave it.
What is sent to the Choo Choo server
- Station codes (for example "LST" for London Liverpool Street) when the app asks for departures. They aren't linked to you.
- Sign-in. In the apps you sign in with Apple; the Claude connector also offers Google. We check that the sign-in is genuine and give the app a token. We don't store your name or email address.
- Your saved trips. So they appear on every device you sign in to, we store each trip's name, its stations and its order. They are filed under a one-way code made from your sign-in, not your name or email, in Google Cloud Firestore in the EU. Your location is never part of a trip: "nearest station" is worked out on each device.
Like most web services, our hosting provider (Google Cloud, in the EU) keeps standard request logs, including IP addresses, for up to 30 days to keep the service running. We don't use them to identify you.
If you use the Choo Choo connector in Claude, we count how the tools are used (which tool, whether it worked, how long it took). The count is keyed to a one-way code made from your sign-in, not your name or email.
What we don't do
No advertising, no tracking across apps or websites, no selling or sharing of data. This website doesn't set cookies for tracking and doesn't load third-party analytics. Fonts are loaded from Google Fonts, which sees your IP address when the page loads.
Where the train data comes from
Departure information comes from the UK rail industry's live data, supplied through a data provider. Station names and locations come from uk-railway-stations by David Wheatley and Trainline EU, under the Open Database License.
How long we keep things
- Saved trips are kept until you delete them or delete your account.
- Request logs are kept for up to 30 days.
- Connector usage counts are kept for up to 400 days, then deleted.
Your rights and contact
The only thing we keep about you is your saved trips. Deleting a trip in the app deletes it from our server too. To delete your account, open Settings in the iPhone or Mac app and choose Delete Account: your saved trips are removed from our server straight away and you're signed out. To stop sending anything, delete the app.
You can ask us for a copy of the data we hold about you, to correct it, or to delete it, by emailing nomukaiki+choochoo@gmail.com. If you think we've got something wrong, you can complain to the Information Commissioner's Office (ico.org.uk).
Changes to this policy
If this policy changes, the new version goes on this page with a new date at the top. If a change is significant, the app will say so.