Cairn — Privacy Policy

Last updated: 31 August 2026

Cairn is a travel packing list app. It builds a packing list for a trip, lets you check things off as you pack, measures a bag against airline size limits, and keeps a record of countries you have visited and want to visit. This policy explains what it does with your data.

The short version: your trips, items, and photos stay on your device and in your own iCloud account. The details of a trip are sent to one AI provider to write the list. There are no accounts, no third-party analytics, no advertising, and nothing is sold.

What Cairn sends off your device

Trip details, when you generate a list. The destination, dates, trip type, luggage type, number of travellers, accommodation type, and planned activities are sent over an encrypted connection to our generation service and from there to Anthropic's Claude API, which writes the list. Our service holds them in memory only for as long as that one request takes. They are never written to our storage and never written to our logs.

Anthropic processes those details to generate the list. Their handling of API data is governed by their own terms and privacy policy at anthropic.com/legal/privacy.

A device identifier. On first launch Cairn generates a random identifier and stores it on your device. It is sent with each generation request so that requests can be counted against a daily limit and, for subscribers, checked against an active subscription. It is not derived from your hardware, and it is not linked by us to your name, email, or any other identity.

Subscription information. Purchases are handled by Apple and by RevenueCat, our subscription provider, using the same device identifier as the account key. We never see your payment details. RevenueCat's policy: revenuecat.com/privacy.

What stays on your device and in your iCloud

• Your trips and packing items — names, destinations, dates, quantities, notes, and what you have checked off.
• Trip photos you choose from your photo library.
• Countries you mark as visited or want to visit, and the passport card generated from them.
• Your settings, including the light or dark appearance and the airline you last measured against.

All of this is stored in the app's private storage and synced through Apple's CloudKit into your own private iCloud database. It is covered by Apple's privacy policy, and we have no access to it. If you turn off iCloud for Cairn, the data simply stays on the device.

The camera and the bag measure

Measuring a bag uses the camera. The camera feed is processed live on your device by Apple's ARKit so that tapping a corner can be turned into a position in space. No frame of that video is recorded, stored, or sent anywhere. The only result is three measurements, which are shown on screen and are not saved.

Your photo library

When you add a photo to a trip, iOS shows its own picker and hands Cairn only the single image you chose. Cairn never receives access to the rest of your library.

What Cairn does not do

• No accounts. Cairn never asks for your name, email, or phone number.
• No third-party analytics and no advertising SDKs of any kind.
• No tracking across other apps or websites. Cairn has nothing to track with, which is why iOS never shows you a tracking permission prompt for it.
• No selling or sharing of personal data with data brokers.
• No location access. Destinations are text you type, not places we look up.

Children

Cairn is not directed at children under 13 and does not knowingly collect information from them.

Your choices and deleting your data

Because Cairn has no accounts and keeps no server-side copy of your trips, your data is under your direct control. Deleting the app removes the local copies. Turning off or clearing Cairn's iCloud data in iOS Settings removes the synced copy. Cancelling a subscription is done through your Apple account.

To ask a question about this policy, or about anything else, contact loqqty0525@gmail.com.

Depending on where you live you may have rights to access, correct, delete, or restrict processing of your personal data, and to complain to a data protection authority. Write to the address above and we will respond.

Changes

If this policy changes, the date at the top changes and the current version is always at this URL.