TezStudio KO
PRIVACY POLICY

사주문

Last updated · 2026-11-02

1. Overview

TezStudio ("the Studio") respects user privacy in Sajumoon (SajuAI) and its web service at saju.tez.kr (together, "the App") and handles personal data in accordance with applicable laws including South Korea's Personal Information Protection Act and GDPR.

SajuAI is a learning and self-reflection platform for traditional Korean Saju Myeongnihak (Four Pillars of Destiny). We collect only the minimum personal data necessary to derive a user's chart and provide AI-powered consultation.

2. Information We Collect

2-1. Saju analysis data

  • Name (optional, nickname accepted) — for displaying analysis results
  • Date and time of birth — required to compute the chart
  • Gender — used in interpretation
  • Birthplace (optional) — used for precise solar-term correction
  • Lunar/solar calendar selection
  • Relationship profiles — Saju information of partners or family members the user voluntarily registers, used for compatibility analysis

Note: When entering another person's information (name, date of birth, etc.) for compatibility or relationship analysis, you must obtain that person's consent in advance.

2-2. Account data

  • Apple/Google ID or anonymous guest identifier — Firebase Authentication
  • Email address — provided by Apple/Google sign-in, or entered at email sign-up (passwords are stored encrypted by Firebase and are never visible to the Studio)
  • Display name — automatically provided by social sign-in

2-3. Purchase data

  • Purchase receipts and transaction IDs — Apple App Store / Google Play in-app purchases
  • Web payment records — when paying on the web (saju.tez.kr): order ID, payment key, amount, payment method, and approval time (via the PortOne integration module connecting to the KG INICIS checkout)
  • The Studio never accesses card details; payments are processed by Apple/Google or KG INICIS.

2-4. Usage data and advertising identifiers

  • Analysis results, chat history, ticket balance (Firestore)
  • Firebase Analytics (GA4) — app usage events and a random app-instance ID generated per install
  • Android Advertising ID (AD_ID) — collected on Android as an analytics signal. On iOS, the IDFA is not collected.
  • On the web: visit and usage records, cookies, browser/device information, and IP address (Google Analytics). Cookies can be refused in browser settings.

Opting out of Android Advertising ID — on the device, go to Settings > Privacy > Ads > "Delete advertising ID" (depending on device and Android version, this may appear under Settings > Google > Ads). Once deleted, the Advertising ID is replaced with a zeroed-out value, so it cannot be linked to analytics. All app features remain available after opting out.

3. AI Services (Important) — Explicit Consent Required

SajuAI uses OpenAI's GPT models to power Saju analysis, AI fortune teller chat, and image-based face/palm reading. A consent sheet is shown on first use of the AI features, and the data below is sent to OpenAI via our servers (Firebase Cloud Functions, Seoul) only after you explicitly consent. See Section 7 "Cross-Border Data Transfer" for the full list of transferred items, retention, and how to withdraw consent.

  • Data reaches OpenAI only at request time; after the response is received, OpenAI handles it per its API policy (up to 30 days, no training use).
  • Face and palm photos are used only for the single analysis request and are not permanently retained by either the Studio or OpenAI.
  • Withdrawing consent — turn off the "AI Transfer Consent" toggle in the app's "Me" tab → Settings, or email supports@tez.kr. After withdrawal, only the AI features (Saju analysis, AI fortune teller chat, face/palm image reading, auspicious date selection, naming, dream interpretation, etc.) become unavailable; features that do not use AI (Manseryeok chart, today's almanac, etc.) continue to work normally.

4. Data Storage and Location

  • Google Firebase Firestore — hosted on Google Cloud (US / AS regions). Stores section 2-1 (name, date and time of birth, gender, birthplace, lunar/solar flag, relationship entries), section 2-2 (account identifier, email, display name), section 2-3 (purchase receipts, transaction IDs, web payment records), and the analysis results, chat history, and ticket balance from section 2-4, isolated per user. Transport is encrypted via HTTPS/TLS and access is controlled by Firebase Security Rules. On account deletion, the Firestore data above is deleted immediately (purchase receipts, transaction IDs, and web payment records are retained for 5 years under Korea's e-commerce law — see Section 8).
  • Google Firebase Authentication — stores the account identifier, email, and encrypted password. Hosted on Google Cloud.
  • Google Cloud Functions — for IAP receipt validation and other server logic (asia-northeast3 / Seoul region).

5. Camera and Photo Access

Camera and photo library access are requested only when the user explicitly invokes the face or palm reading feature. The captured or selected image is sent once to the OpenAI Vision API and discarded immediately afterward; it is not retained on the App or our servers.

6. Third Parties and Sub-Processors

We do not share personal data with third parties except for the following sub-processors:

  • Google LLC — Firebase Authentication, Firestore, Analytics, Cloud Functions
  • OpenAI, L.L.C. (United States) — GPT-based analysis and consultation (see Section 7)
  • Apple Inc. — Sign in with Apple, App Store payments
  • Korea PortOne (PortOne) — web payment integration module (payment-gateway connector)
  • KG INICIS Co., Ltd. — web payment processing (electronic payment service)

7. Cross-Border Data Transfer

Under Article 28-8 of South Korea's Personal Information Protection Act, we disclose the following cross-border transfer. You may decline this transfer; if you do, only the AI features (Saju analysis, AI fortune teller chat, face/palm image reading, auspicious date selection, naming, dream interpretation, etc.) become unavailable, while features that do not use AI (Manseryeok chart, today's almanac, etc.) continue to work normally.

  • Transferee — OpenAI, L.L.C. (contact: privacy@openai.com)
  • Destination country — United States of America
  • Items transferred — name, date and time of birth, gender, birthplace, computed chart values, consultation/question content, name and date of birth of a compatibility partner, dream and name-choosing input text, face/palm photos
  • When and how — at the moment you use an AI feature, routed through our server (Firebase Cloud Functions, asia-northeast3 Seoul) over HTTPS/TLS
  • Purpose — to generate the result of that AI feature
  • Retention — not used by OpenAI for model training; retained for up to 30 days for abuse monitoring under OpenAI API policy, then auto-deleted
  • How to decline / effect — turn off "AI Transfer Consent" in the "Me" tab → Settings, or email supports@tez.kr. After stopping, only the AI features are unavailable; non-AI features continue to work.

8. Retention and Deletion

  • Account data, Saju profile, and chat history are deleted immediately upon account deletion.
  • Purchase receipts and transaction IDs are retained for 5 years per Korea's e-commerce law.
  • Backups: kept for disaster recovery — point-in-time recovery for 7 days and weekly backups for 14 weeks — then deleted automatically. Deleted data may remain in backups for this period and is used only for recovery
  • Uninstalling the App does not automatically delete server data — use in-app account deletion or email us.

9. User Rights

You may request access, correction, deletion, restriction of processing, or withdrawal of consent at any time.

  • Edit or delete profiles directly in My Page → Profile Management.
  • Delete all your data in Settings → Account Deletion.
  • Email requests: supports@tez.kr

10. Children's Privacy

SajuAI is not directed to children under 14. We do not knowingly collect personal data from children. If we discover that a user under 14 has registered, we will promptly delete the associated data.

11. Security

  • TLS 1.2+ encryption in transit
  • Per-user data isolation enforced by Firebase Security Rules
  • API keys and other secrets stored as server environment variables only — never exposed to clients

12. Policy Changes

We will provide advance notice via the App or this page before any material change to this policy. Significant changes may also be communicated via push notification or email.

13. Disclaimer

Saju analysis and AI fortune teller consultations are educational and self-reflective content based on traditional Korean Myeongnihak theory. They do not substitute for professional medical, legal, financial, or other advice.

14. Contact

For privacy inquiries or to exercise your rights, contact supports@tez.kr.