Privacy Policy

Note: This Privacy Policy is provided in Japanese, English, and Korean for reference. The Japanese version is the official governing version. In the event of any conflict or inconsistency between the Japanese version and any translated versions, the Japanese version shall prevail. Official Japanese Privacy Policy

"JunJun - Study SNS" (hereinafter referred to as the "App") establishes the following privacy policy (hereinafter referred to as the "Policy") regarding the handling of users' personal information within the App.

1. Information Collected and Purpose of Use

The App collects the following information and uses it for the respective purposes.

1-1. Information Provided by Users

• Email Address
  • For user authentication (such as sending one-time password emails).
  • To send announcements and important update information regarding the App.
• Profile Information (username, icon settings, etc.) and Study-related Post Data (study time, study materials, comments, etc.)
  • For the provision and operation of the App's services (such as real-time sharing of study status and timeline display).
• Inquiry Content
  • To respond to inquiries and provide support.

1-2. Automatically Collected Information

• IP Address
  • For API rate limiting.
• Purchasing and Billing Information (anonymized identifiers provided through the payment system. We do not directly collect or store payment information such as credit card numbers)
  • For the provision of paid features and billing payment services.

2. Provision of Information to Third Parties and Use of External Services

The App uses the following external services to the extent necessary to achieve the purposes of use. The information collected by these services is managed in accordance with the privacy policies of each respective company.

• Authentication, Notifications, and Email Delivery
  • BetterAuth Purpose of use: User management and understanding of usage statistics.
  • OneSignal (OneSignal, Inc.) Purpose of use: Sending push notifications.
  • Resend (Resend, Inc.) Purpose of use: Sending one-time password emails for login.
• Billing Management
  • RevenueCat (RevenueCat, Inc.) Purpose of use: Management of in-app purchases and subscriptions.
• Ad Delivery
  • Google AdMob (Google LLC) Purpose of use: Delivery of interest-based advertisements within the App. Note: While the App may display ads based on users' interests, we strictly do not perform any "tracking" (tracking user behavior across third-party apps or websites).
• Access Analytics and Crash Reports
  • Apple (App Store), Google (Google Play) Purpose of use: Understanding App usage statistics and analyzing defects.
• Affiliate Programs The App participates in the following programs to introduce products and services, and posts affiliate links. When transitioning to external sites via these links from the App, the link includes an identifier indicating that it is a transition from the App. While this may result in the collection of information by the destination site, the App does not directly provide these business operators with information that identifies individual users (such as email addresses).
  • Rakuten Affiliate (Rakuten Group, Inc.)
  • Amazon Associates (Amazon.com, Inc. or its affiliates)
  • ValueCommerce Affiliate (ValueCommerce Co., Ltd.)

Except as required by law, the App will not provide personal information to third parties other than those listed above without obtaining the user's prior consent.

3. Deletion of User Data (Account Withdrawal)

Users can delete their accounts at any time by using the account withdrawal feature within the App. When the withdrawal process is executed, all user data, including the user's profile information and post data, is immediately and permanently deleted from the system (physical deletion) and cannot be restored.

4. Source Code Disclosure and Ensuring Transparency

In order to ensure transparency regarding the handling of user data, the App makes the source code of both the app and the server publicly available on GitHub. If you have any concerns about how data is handled or how the system works, anyone can verify the actual processing details (code).

• Server API: https://github.com/oyajun/stajun-server
• iOS App: https://github.com/oyajun/stajun-ios

5. Changes to the Privacy Policy

The App may change this Policy as necessary. The updated Privacy Policy will take effect from the time it is posted within the App or on a designated website.

6. Contact Information

For inquiries regarding this Policy, please contact the following email address.

• Contact: [email protected]

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Date of Enactment: August 4, 2026