Kaartje Privacy Policy

Last updated: 11 July 2026

Kaartje is an indie app made by Luuk van Baars. It's built around a simple idea: the cards you keep are personal, and what's on them should stay between you and the people who sent them. This page describes what information the app handles, where it goes, and what it never does.

If anything here is unclear, email luukvanbaars@gmail.com.

What Kaartje stores

Everything you scan stays on your device and (if you have iCloud Drive enabled) in your own private iCloud container. We do not run a server that holds your cards, and we cannot read them.

Specifically, Kaartje stores:

Card images — front, inside, and back photos of the cards you scan. Saved as image files in the app's Documents folder on your device, and mirrored into your iCloud Drive container if iCloud is enabled.
Card metadata — the date you received the card, the sender name you typed, the category, free-form notes, and any moment you assigned the card to. Saved alongside the images.
Search index (OCR text) — when you save a card, Kaartje runs text recognition on the images using Apple's on-device Vision framework. The recognised text is stored with the card so the search bar can find it. The text never leaves your device or iCloud container.
Custom categories — any category names you create are stored as a JSON file in your iCloud container so they sync across your devices.

All of the above lives in your own device storage and your own iCloud account. The developer has no access to it.

What Kaartje sends off-device

Kaartje sends a small amount of anonymous usage data to a Google Apps Script endpoint so the developer can understand how the app is performing and which fixes to prioritise. None of it contains card images, card text, sender names, notes, or anything else you typed.

Each event carries:

What happened — short markers like scan started, outside scanned, saved, abandoned, app opened, search used, card opened, card edited, paywall shown, moment created, category created, or purchase completed. Just the marker — when you create a category or moment, its name is not included.
Basic card facts on save — the card type (postcard, vertical fold, horizontal fold), whether it was die-cut, whether a sender was filled in (only yes/no — never the name), and the category. If the category is one you created yourself, the app reports only the word "custom" — the name you typed never leaves your device.
Country and time zone — derived from the device locale (not GPS). Used to see roughly where the app is being used.
A randomly-generated device identifier — a UUID created the first time the app launches. Used to count distinct users without knowing who they are. Not linked to your Apple ID, email, name, or any other identifier.
Device model, iOS version, and app version — e.g. iPhone 15 Pro, iOS 18.2, 3.0 (461). Used to reproduce bugs.
Your plan — which unlock tier the device is on (free, up to 20, up to 100, or unlimited). Used to understand how each plan is used.

This data collection is part of using Kaartje — there isn't a toggle to turn it off. If you'd rather not send it, the only option is to not use the app. The trade-off is intentional: the events are small, anonymous, and the only way a one-person indie app like this gets the feedback it needs to improve.

What Kaartje never collects

Your name, email address, phone number, or Apple ID
Your precise location (no GPS access is requested)
Any analytics tied back to a specific person
Card images or card text (these never leave your device or iCloud)
Anything you typed — sender names, notes, titles, and custom category names stay on your device
Anything from your photo library — Kaartje never requests photo access; it only uses the camera

Kaartje has no account system. There is nothing to sign up for and nothing to log in to.

Optional permissions

A few features need iOS permission prompts. Each one is optional — the app works without granting them, you'll just lose that specific feature.

Camera — required to scan cards. Without it, you can't add cards through the camera flow.
Contacts — entirely optional. If you grant access, the "From" field on a new card suggests names from your address book as you type. Names matched this way are used only on your device to populate the autocomplete list. Nothing is uploaded.

iCloud

If iCloud Drive is enabled on your device, Kaartje automatically mirrors your card library to your private iCloud container. This lets your cards appear on your other Apple devices signed in to the same Apple ID.

iCloud storage is provided by Apple under your Apple ID. Kaartje does not have its own server. If you want to stop syncing, sign out of iCloud or disable iCloud Drive for Kaartje in iOS Settings.

In-app purchases

Kaartje offers three one-time purchases that raise how many cards you can keep: Up to 20 Cards, Up to 100 Cards, and Kaartje Unlimited (which also unlocks the home-screen widget). Each is a one-time purchase, not a subscription.

All purchases are processed by Apple through the App Store. Apple is the merchant of record and handles the payment, the receipt, and any refunds. Kaartje does not see your payment details.

Purchases are tied to your Apple ID, not to a Kaartje account (there is no Kaartje account). Restoring purchases on a new device re-checks your Apple ID's purchase history.

Third-party services

Kaartje uses two outside services:

Apple iCloud — for syncing your card library across your devices. Governed by Apple's iCloud Terms.
Google Apps Script — receives the anonymous usage events described above. Hosted on Google's infrastructure under the developer's account. Governed by Google's Privacy Policy.

No other third-party services receive your data.

Children

Kaartje is not directed at children under 13 and does not knowingly collect data from them. If you believe a child has used the app and sent data, contact luukvanbaars@gmail.com and we'll delete it.

Your rights

Because Kaartje does not hold your data on a server, most "data rights" requests are something you can act on yourself:

Delete a card — long-press a card in the list and choose Delete. The card and its images are removed from your device and your iCloud container.
Delete everything — delete the Kaartje app from your device. This removes the local copy. To also remove the iCloud copy, go to iOS Settings → your name → iCloud → Manage Account Storage → Kaartje → Delete Data.

If you have questions about your data — including the anonymous usage events — email luukvanbaars@gmail.com and we'll help where we can.

Changes to this policy

If this policy changes in any meaningful way, the "Last updated" date at the top will change and a notice will appear in the app the next time you open it.