Privacy — Chart
chart.boating.systems · last updated 26 August 2026
Chart runs on your device. Your position is used to draw the boat on the map and is not sent to us. Nothing you record leaves the phone unless you sign in, and nothing you record is visible to anyone else unless you publish it yourself.
Who we are
Chart is part of boating.systems, run by JR Logan. Questions, corrections, or a request to delete your data: johnrichardlogan@gmail.com.
Location
Chart asks for location so it can show where your boat is on the chart, report your speed and course, and colour the water against your draft. Location is used while the app is open; Chart does not request background-location permission and does not track you when the app is closed.
- On the device. Your track — the line behind the boat — is held on the phone. Depending on your settings it either fades after about 45 minutes or is saved to the app's local storage so you can look at the outing later.
- Sent to us only if you sign in. When you are signed in, a finished outing is uploaded to your own private account so it appears in the Log app on your other devices. Signed out, no track ever leaves the phone.
- Sent to weather services. To fetch a wind forecast, Chart asks the US National Weather Service for the forecast grid covering your position, which means your approximate position is sent to weather.gov. Tide and current predictions are fetched by station identifier, not by your position.
- Visible to map servers. Chart requests map tiles for the area you are looking at from our servers and, for the optional OpenStreetMap and OpenSeaMap layers, from theirs. Like any web request, that reveals the area being viewed and your IP address to the server answering it.
What we store when you sign in
Signing in is optional. Chart works fully without an account; signing in is what lets your boats, settings and outings follow you to another device.
| Data | Why | Who can see it |
|---|---|---|
| Your Google account identifier and email address | To recognise you across devices and apps | You and the operator |
| Your boats (name, draft, air draft) | To colour depths against your keel | You |
| App settings (units, safety margin, display mode) | To keep the app set up the way you left it | You |
| Outings — track points, times, speeds, and the boat they belong to | So the Log app can show them | You, unless you publish one — see How we use what you record |
Trips are private when created. Publishing one is a separate, deliberate act that makes that trip readable by anyone who has its link — it is never listed or searchable, and unpublishing closes access again immediately.
How we use what you record
Beyond showing your outings back to you, we may study track data to make the service better — for example to find anchorages, moorings and channels that belong in the Guide, to check charted depths against where boats actually go, and to improve the apps. Where that work does not need to know whose track it is, we use it aggregated and stripped of identifying detail.
Two things this never means. It is never what makes a trip public: sharing is yours to choose. A trip is private when it is created, becomes readable by other people only when you share it, and stops being readable the moment you unshare it. And we do not sell your data.
What we do not do
- No advertising, and no ad identifiers.
- No analytics or tracking SDKs. Chart ships with none.
- No selling or sharing of personal data with third parties for their own purposes.
- No account required to use the app.
Processors
We use Google Firebase (Authentication, Firestore, Cloud Storage, Cloud Functions and Hosting) to run the service and store the data described above on our behalf. See Firebase's privacy documentation. Chart also reads public forecast data from NOAA and the US National Weather Service, and optional map layers from OpenStreetMap and OpenSeaMap.
Keeping and deleting your data
Data on your device is removed when you uninstall the app or clear its storage. Outings you have uploaded are kept until you delete them: each trip can be deleted from the Log app. To delete your account and everything attached to it, email johnrichardlogan@gmail.com and we will remove it.
Children
Chart is not directed at children under 13 and we do not knowingly collect their data.
Changes
If this policy changes materially we will update the date at the top and, for anything that affects what leaves your device, say so in the app's release notes.
Safety
Chart is not a certified navigation system and must not be used as your primary means of navigation. Charted data may be incomplete, out of date, or wrong, and predictions are predictions. Carry official charts and keep a proper lookout.