Privacy Policy
The short version: Rainbow’s Arc collects no data. Nothing you enter, and no photo you take, ever leaves your device.
What the app stores, and where
Everything you put into Rainbow’s Arc — voyages, dead-reckoning legs, sights, fixes, your height of eye and camera settings — is stored only in the app’s local storage on your own device. It is never transmitted anywhere, because there is nowhere to transmit it: the app has no server, no account system, and makes no network requests.
Deleting the app deletes this data. If you back up your device, your backup may include the app’s data like any other app’s; those backups are managed by Apple under their own terms, and we never see them.
Camera and photos
The app asks for camera access so you can photograph the sun and the horizon, and for photo library access so you can use a picture you already took. Every photo is processed entirely on the device — the app measures angles from it and reads its embedded time stamp, then keeps only the numbers of the sight in your local log. Photos are never uploaded, analyzed remotely, or shared with anyone.
Location — only when you ask
The app asks for your location for three things, and only when you tap them:
- The sextant drill, which scores a sight taken with a real sextant against where you are.
- The deck log’s “Check against GPS,” which grades your dead reckoning and shows the set and drift the gap implies.
- Starting the reckoning from where you are: “Read the GPS aboard once,” or “Restart the dead reckoning from the GPS position.”
A reading is used for the comparison on screen and then discarded, unless you choose to start the reckoning from it. Then it is kept on your phone as that voyage’s starting point, like a position you typed. It is never sent anywhere. Decline the permission and the drill scores against your dead reckoning instead, the GPS check reports that there is nothing to compare against, and you type the starting point yourself.
What the app does not do
Rainbow’s Arc contains no analytics, no advertising, no tracking of any kind, and no third-party data-collection software. It does not track your location — the three uses above happen only when you tap them. It does not read your contacts or anything else on your device beyond the photos you deliberately hand it. It works entirely offline — by design, because a boat is often out of signal.
Purchases
Buying the app is handled entirely by the App Store. We receive no payment details, no card numbers, and no personal information from your purchase.
Children
The app collects no data from anyone, children included.
Changes to this policy
If a future version of the app ever changes any of the above — for example, by adding an online feature — this policy will be updated first, with the effective date above revised, and the change described plainly rather than buried.
Changes so far
October 4, 2026: the location section now names a third use, starting the reckoning from where you are, and says plainly that a reading you start from is kept on your phone as the voyage’s starting point. An earlier version said no reading was ever stored; that was wrong for this one case since the first release. Nothing has ever left your phone, and the app still collects nothing.
September 9, 2026: “What the app does not do” now names both on-the-spot uses of location — the sextant drill and the deck log’s GPS check — as the section above it already did. Nothing about what the app collects has changed: still nothing.
Contact
Questions about this policy: support@RainbowsEndMarine.com.
Rainbow’s Arc is for fun and for practice, not a substitute for judgment or for the navigation the law requires of you — see the notes inside the app.