Privacy Policy

This page is an English translation of the Japanese version. If there is any discrepancy, the Japanese version prevails.

Last updated: September 2026

Kashikoi Bookshelf (the “App”) respects your privacy and strives to protect your personal information. This Privacy Policy explains what information the App collects, how it is used, and your rights.

1. Information we collect

1.1 Location

The App uses your location (latitude and longitude) to search for libraries near you.

• When it is collected: Only when you use the library search feature
• Where it is stored: Location is stored temporarily on your device and is not sent to the developer’s servers
• Purpose: Only to search for nearby libraries through the Calil API
• Disclosure to third parties: Location is sent to the Calil API, but not in a form that identifies you

1.2 Camera data

The App uses the camera to scan ISBN barcodes on books.

• When it is collected: Only when you use the barcode scanning feature
• Where it is stored: Camera images are processed on your device and are not saved
• Purpose: Only to read ISBNs
• Disclosure to third parties: None

1.3 Book data

The App stores the book information you register.

• What is stored: Book title, author, ISBN, publisher, cover image URL, favorite library information, and similar
• Where it is stored: The local database on your device (SwiftData) and iCloud (optional)
• Purpose: Providing the bookshelf feature and syncing data across your devices
• Disclosure to third parties: None
• iCloud sync: If you are signed in to iCloud, your data is synced automatically to Apple’s private cloud database

2. How we use information

Collected information is used only for the following purposes.

1. Searching for and displaying nearby libraries
2. Reading book ISBN barcodes
3. Managing and displaying your bookshelf
4. Improving the App and fixing bugs
5. Displaying ads

3. Third-party services

The App uses the following third-party services.

3.1 Rakuten Books API

• Provider: Rakuten Group, Inc.
• Purpose: Retrieving book information based on ISBNs and keywords
• Data sent: ISBNs and search keywords
• Privacy policy: Rakuten Group privacy policy

3.2 Calil API

• Provider: Calil, Inc.
• Purpose: Searching library holdings and nearby libraries
• Data sent: ISBNs, location (latitude and longitude), and library system IDs
• Privacy policy: Calil privacy policy

3.3 Affiliate links

The App participates in the Rakuten Books and Amazon affiliate programs. If you buy a book through a link in the App, the developer may receive a commission. These services may use their own cookies and tracking technologies.

3.4 Advertising (Google AdMob)

• Provider: Google LLC
• Purpose: Displaying ads (banner ads) in the App and measuring ad performance
• Data collected and sent: Advertising identifier (IDFA), device information, approximate location inferred from your IP address, and information about ad impressions and interactions
• Managing consent: In the EEA, the UK, and some other regions, you can choose in the consent form (Google’s consent management platform) shown at first launch. You can change your choice at any time from “Ad privacy settings” in Settings.
• Tracking permission: The advertising identifier (IDFA) is used only if you allow tracking in the iOS tracking permission dialog. You can use the App in the same way if you do not allow it (the ads shown will be less relevant).
• Privacy policy: Google Privacy Policy, Google advertising policies

4. Data storage and management

4.1 Where data is stored

• Your data is stored locally on your device
• The App does not operate its own servers and does not send or store user data on the developer’s servers (transmission to third-party services is as described in “3. Third-party services”)

4.2 Data security

• Your data is protected by your device’s security features (passcode, Face ID, Touch ID, etc.)
• Data may be included in encrypted iCloud backups

4.3 Retention

• Data is kept until you uninstall the App
• Data on your device is deleted automatically when you uninstall the App (data in iCloud follows your iCloud settings)

5. Your rights

5.1 Managing permissions

You can change the following permissions at any time in iOS Settings.

• Location: Settings > Privacy & Security > Location Services > Kashikoi Bookshelf
• Camera: Settings > Privacy & Security > Camera > Kashikoi Bookshelf
• Tracking: Settings > Privacy & Security > Tracking > Kashikoi Bookshelf

If you deny a permission, the related features (library search, barcode scanning) become unavailable, but the other features remain available.

5.2 Deleting data

Uninstalling the App deletes all data on your device.

6. Children’s privacy

The App does not knowingly collect personal information from children under 13. If you are a parent or guardian and believe your child has provided personal information through the App, please contact us using the information below. We will respond promptly.

7. Changes to this Privacy Policy

We may update this Privacy Policy as needed. The latest version is always available on this page.

8. Contact

If you have any questions or comments about this Privacy Policy, please open an issue on GitHub Issues. Issues are public, so please do not include personal information.

• Developer: Naoyuki Sato

9. Governing law

This Privacy Policy is governed by and construed in accordance with the laws of Japan.