Privacy Policy

App Design Lab (iOS) · Effective October 20, 2026

1. Data we collect

No personal data. The app contains no third-party SDKs, does not use the advertising identifier (IDFA), and does not access location, contacts, photos, or the camera. The only data that leaves your device is listed under "Anonymous usage statistics" below, plus any feedback you choose to send yourself (section 3).

Anonymous usage statistics

To learn how many people use the app and to fix crashes, the app sends the following anonymous statistics to Apple's iCloud (CloudKit), where only the developer can read them:

• A random ID created when the app is installed (not linked to you, your Apple ID, your device, or other apps; it changes if you reinstall)
• App version, iOS version, and region and language settings
• How many times the app was opened and the days it was opened, the install date, and the number of days since install
• Reports of crashes and unexpected quits (app version, iOS version, device type, and technical details of the error)

No name, contact details, location, or anything you create, such as study notes or quiz results, is included. Statistics are sent only while you are signed in to iCloud. They are sent by LeeoKit, a shared library written by the developer, and are never passed to third parties.

2. Data stored only on your device

So you can pick up where you left off, the following is stored on your device only and is never transmitted to anyone, including the developer:

• Lesson progress and the study notes you write in lessons
• Quiz results, labs you have visited, and mistakes you have checked off

This data is removed when you delete the app. If device backups (such as iCloud Backup) are turned on, it may be included in those backups under Apple's backup policies.

3. When you export something yourself

• Copy: copying study notes or sample code places them on the device clipboard.
• Share: exporting study notes as a Markdown file opens the iOS share sheet. You choose where it goes; the app is not involved in what happens after that.
• Send Feedback: when you tap send in Settings › Send Feedback, the text you wrote, along with the app version, iOS version, and device type, is sent to Apple's iCloud (CloudKit), where only the developer can read it. Your name and contact details are not requested, and replies appear inside the app.
• Email and Instagram: the contact rows in Settings open your device's Mail app or Instagram. What happens after that is governed by each service's policy.

4. In-app purchases

Payment for Pro subscriptions and the lifetime purchase is handled by Apple through the App Store. Neither the app nor the developer receives your card number or payment details. To check whether Pro is unlocked, the app reads only the purchase record Apple provides on your device, and the result stays on your device.

5. External links

Reference links (Apple Developer documentation, blogs, and so on) open in your device's browser, such as Safari. Those sites handle information under their own policies.

6. Children's privacy

The app does not collect personal data from users of any age. The anonymous usage statistics cannot be traced back to anyone.

7. Changes to this policy

If the way the app handles data changes, this page will be updated first and given a new effective date.

8. Contact

For privacy questions, email leeo@kakao.com or open an issue on GitHub Issues.