Privacy Policy

Effective 31 October 2026 · This English text is a translation for convenience; the Korean version governs.

History: 31 October 2026 Added parental consent sign-up for children under 14, Kakao, passkey, QR and email-link sign-in, and the free trial, family plan, student discount, gift codes, acorn discount and their refund rules / 18 October 2026 First version

1. Data we collect

• World pine forest (optional): planting spot (about 50 m) and neighbourhood name, nickname, tree name and special day, guestbook messages, cheer signs, friend code. Nicknames, tree names, messages, signs and planting spots are visible to all users.
• Email sign-up: email, password (stored hashed), name (optional).
• Google sign-up: email, name, Google account identifier.
• Kakao sign-up and sign-in: Kakao member number, nickname, and email (only if you agree to share it in Kakao).
• Passkeys (optional): passkey identifier, public key, signature counter, device name (e.g. Windows · Chrome), creation and last-used dates. Biometric data (fingerprint, face) and the private key stay on your device and are never sent to or stored by the Company.
• QR sign-in: the requesting computer’s device type (operating system and browser name) and country, kept only in the 2-minute one-time request to show on your phone, and the approving account.
• Email sign-in links: a hash of the one-time link (valid 15 minutes; the link itself is not stored).
• Members under 14: the parent’s or guardian’s email (used only to send the consent request; not stored) and the consent record (time of consent and a hash of the guardian’s email).
• Using the Service: study history (time, expressions learned, review state, progress), language and study settings, country (estimated from IP), access time.
• AI Tutor: the messages you type (used only to generate answers; not shown in admin screens).
• Payments: Paddle processes payment details; the Company never stores card numbers. We keep payment results and subscription status (Paddle customer and subscription IDs).
• Business enquiries: organisation name, contact name, work email, phone, business registration number, representative, address, invoice email.

2. Why we use it

• Identifying members, sign-in (including Kakao, passkeys, QR and email links), saving and syncing study history across devices.
• Confirming and recording parental consent for children under 14.
• AI-based course planning and learning analysis.
• Giving organisation admins team-wide usage totals (seats in use, total study time) — never per-member study records
• Providing paid plans, renewals, settlement, invoices and receipts.
• Answering enquiries, sending notices and preventing abuse.

3. Retention

• Account data: until the account is deleted (deleted immediately), except where Korean law requires keeping records: contracts and withdrawals 5 years, payments 5 years, complaints and disputes 3 years, access logs 3 months.
• Sign-in methods (Kakao link, passkey public keys) and parental consent records: until the account is deleted. Deleting a passkey removes it immediately.
• One-time sign-in values (email links, QR codes, passkey challenges) stop working after 15 minutes, 2 minutes or 5 minutes and are deleted periodically afterwards.
• Sign-up requests from children under 14 are deleted without delay if the guardian declines or does not consent within 7 days.

4. Processors and transfers abroad

• Cloudflare, Inc. (USA and data-centre countries): hosting, database and file storage.
• OpenStreetMap Nominatim: neighbourhood names for planting spots and place search (only coordinates or the search text are sent, never account details).
• OpenFreeMap (OpenStreetMap data) and unpkg: map tiles and the map library for the world pine map. When you view the map your browser connects to these servers and your IP address may be shared. Planting spots are stored only to about 50 m, and we never collect your location (GPS).
• Google LLC (USA): AI speech, AI Tutor answers (Gemini API), Google sign-in.
• Kakao Corp. (Korea): Kakao sign-in (Kakao passes the member number, nickname and, if you agree, email to the Company).
• Paddle.com Market Ltd (UK): processing personal subscriptions as reseller.
• Resend, Inc. (USA): password-reset, verification, email sign-in link and parental consent emails (recipient address and message).
• Data is transferred over the network when you use the feature. You may refuse, but the related features (sign-in, payment, AI) will not work.

5. Your rights

• You can ask at any time to access, correct, delete or stop processing your personal data, and we act without delay. Contact: email solhyang98@gmail.com, phone 010-2565-1537, the "Send feedback" button in the app

6. Deletion

• Data whose retention period has ended or whose purpose is fulfilled is destroyed without delay in a way that cannot be recovered.

7. Security

• One-way password hashing (PBKDF2), HTTPS everywhere, least-privilege access, sign-in attempt limits.
• One-time sign-in values (sessions, email links, QR codes, passkey challenges) are stored only as hashes and become invalid once used; passkeys use public-key cryptography, so the server holds only the public key.

8. Cookies

• A session cookie keeps you signed in. You can block it in your browser, but features that need sign-in will not work. Some study settings are kept in your browser (localStorage).
• We use no advertising or tracking cookies and no session-replay or heatmap tools. Usage statistics are counted without cookies (including Cloudflare Web Analytics). Fonts are served from our own server, so no visit data goes to an outside font service.

8-2. Children

• We process personal data of children under 14 only with the consent of a parent or legal guardian (Korean Personal Information Protection Act, Article 22-2; under 13 in the United States). We email the guardian a consent request and activate the account only after they review what we collect, why and for how long, and agree. The child cannot sign in before that.
• The guardian’s email is used only to send the request and is not stored; as proof of consent we keep the time of consent and a hash of the guardian’s email.
• If the guardian declines or does not consent within 7 days, the request and the child’s data are deleted without delay. If we learn that we hold data of a child under 14 without consent, we delete it without delay.
• Guardians can ask at any time, using the contact below, to access, correct, delete or stop processing the child’s data, or withdraw consent.

9. Privacy officer

• Solhyang Design, 김시현 · email solhyang98@gmail.com, phone 010-2565-1537, the "Send feedback" button in the app