Privacy Policy

• Published and effective: September 11, 2026
• Version: 2026-09-11

Eunhasu, represented by Kyounghwan Jung (the “Service”), processes personal information under the Korean Personal Information Protection Act (PIPA) and other applicable laws. Passwords are stored as Argon2id hashes, and account email, purchase tokens, and support content are encrypted at rest. We use Google/Apple login and payments, AdMob, Cloudflare servers and network, Neon PostgreSQL, Brevo email, and Firebase Cloud Messaging (FCM). We collect our own usage and diagnostic information but do not use Google Analytics.

1. Purposes, categories, and legal bases

• Device accounts: app-generated device account identifier, internal user ID, and country derived from the connection IP, for account identification, sessions, entitlements, and abuse prevention. Basis: PIPA Article 15(1)(4), contract formation/performance.
• Email accounts: email, password hash, verification status/time, and optional nickname for registration, login, security, and recovery. Older apps could submit an optional birth year; it is not used for age verification and is no longer saved at signup. Basis: contract formation/performance.
• Google login: Google subject ID, email, provider, and nickname if supplied, for login and linking. Basis: contract performance.
• Apple login: subject ID, email or private relay address, initially supplied name, authentication/refresh tokens, and relay status for login, linking, deletion, and relay handling. Basis: contract performance.
• Restricted-content age verification: date of birth and derived birth year, Duplication Information (DI), provider, and verification time, for age-15/19 eligibility and abuse prevention. Name, telephone number, carrier, gender, nationality classification, and CI are processed temporarily during verification and not saved in our database. Basis: contract performance. Verification uses NHN KCP, including PASS; resident registration numbers are not collected.
• Consent evidence: choice type, policy version, agreement/withdrawal, time, whether the app confirmed the displayed document version, IP address, and User-Agent, to verify consent and handle disputes. Basis: contract performance and legitimate interests under Article 15(1)(6).
• Content and community: user/work/episode IDs, reading and completion status, progress, private reading notes, selected passages, highlights, memo text, locations and colors, favorites, ratings, attendance, achievements, Gem balances/transactions/access grants, content-delivery fingerprints and first/latest delivery times and counts, nickname, comments, reports, blocks, and moderation records. Purposes: content delivery/synchronization, account benefits, community operation, copyright protection, and leak investigation. Basis: contract performance and legitimate interests. A delivery fingerprint does not embed the raw account number but remains linkable personal information.
• Payments and ad-reward settlement: product ID, Google purchase token or signed App Store transaction JWS, order/transaction IDs, payment status/time, Gems credited, refunds, cancellations, recovery-review records, and ad/reward settlement records. Purposes: verification, delivery, refunds, and abuse prevention. Bases: contract performance, legitimate interests, and Article 15(1)(2) with Article 6 of the Electronic Commerce Consumer Protection Act for statutory transaction retention. Advertising SDK collection is separately described in section 8.
• Service notifications: user ID, push token, device platform, work subscriptions, notification content, delivery/read status, for requested work alerts and account, purchase, or operational notices. Basis: contract performance. Marketing is handled separately.
• Optional marketing: email, push token, user ID, and consent/withdrawal status/time, for new-release, event, and discount messages. Basis: consent under Article 15(1)(1) and Article 50 of the Information and Communications Network Act.
• Support and reliability: email, inquiry category/title/message/reply, optional deletion reason, random installation/session IDs, event type, work/episode/product IDs, ad/payment steps and error codes, app version, OS/device model, error messages/stacks/context, IP and access logs. Purposes: support, deletion requests, usage analysis, troubleshooting, performance, and security. Basis: contract performance and legitimate interests.

We do not directly collect payment-card or bank-account numbers. App stores process payment instruments and provide purchase-verification information. Do not include unnecessary sensitive identifiers, financial information, or passwords in comments, inquiries, or error reports.

2. Retention periods

Service data, statutory transaction records, and limited dispute evidence have different retention rules. Statutory periods do not automatically apply to every category.

• Account and identity data, reading state/notes, favorites/ratings, push tokens, subscriptions, and notification inbox: until account deletion, when they are removed.
• Comment, reply, and review bodies: removed when the user deletes them or closes the account. Empty structural links may remain for other users' replies.
• Usage events and app diagnostics: one year from collection; aggregated recurring errors, one year from the last occurrence. Records linked to a deleted account are removed earlier on deletion.
• Content-delivery fingerprints and user/work/episode links: 180 days from the last delivery, for limited copyright investigation. These are not fully anonymous.
• Signup/withdrawal and ad-privacy choice evidence: account lifetime plus three years after deletion, based on legitimate interests in checking lawfulness and resolving actual disputes, rather than a blanket statutory three-year obligation. Necessity, access, and data scope are restricted; objections and processing-suspension requests are reviewed.
• Marketing delivery information: removed from marketing targets on withdrawal or account deletion. The same email/token may remain separately necessary for account or service notifications, without reuse for advertising.
• Consumer complaint/dispute records: three years after resolution, under Article 6 of the Electronic Commerce Consumer Protection Act and Article 6 of its Enforcement Decree.
• General inquiries and account-deletion records: three years after resolution, limited to necessary contact/request/outcome evidence, on the basis of legitimate interests.
• Contract/withdrawal and payment/supply records: five years from the relevant transaction record, under the same legislation, limited to necessary purchase/refund evidence. Data necessary to honor continuing access rights is retained separately during contract performance.
• Display/advertising records: six months from the end of publication under the same legislation; this does not mean collecting individual advertising IDs for six months.
• Temporary email-verification, password-reset, and identity-verification requests: cleared within one day after expiry. Identity-verification validity is one year from verification and differs from the retention period of the result.

A specific investigation or legal proceeding may require limited further preservation. The case, reason, scope, and expected end date are recorded; data is deleted promptly when no longer needed. A hypothetical future dispute does not justify indefinite retention of all data.

3. Disclosures and independent collection by external services

We do not sell personal information or request blanket third-party-disclosure consent at signup merely because payment or identity providers are involved. A new disclosure without another legal basis requires separate notice and consent covering recipient, purpose, categories, retention, refusal rights, and consequences.

Google and Apple login provide us with account information selected on their own authorization screens. Verification sends the necessary authorization codes/tokens and request information to the provider. Google Play and App Store directly collect payment instruments and independently process payment; the Service exchanges purchase/refund tokens and transaction information for verification. These activities are not all classified as simple processing on our behalf.

AdMob may directly collect device information through its SDK. Google's independent processing is subject to its notices and choices. Advertising revenue or non-personalized settings do not by themselves make all ad processing/transfers contractually necessary or exempt from consent. Processing requiring consent must not occur without that consent. ATT approval or tapping a rewarded-ad button is not blanket consent to separate disclosure or overseas transfer.

Google notice and contact: https://policies.google.com/privacy?hl=en and https://support.google.com/policies/troubleshooter/2990837?hl=en Apple notice and contact: https://www.apple.com/kr/legal/privacy/kr/ and https://www.apple.com/privacy/contact/

4. Processing entrusted to providers

• Cloudflare, Inc.: website/API hosting through Workers and Containers, CDN, network, and security. It processes account, identity, consent, content-use, community, purchase-verification, and support information handled through web/API requests, plus IP, requests, and access logs—not just CDN logs.
• Neon, LLC (Neon/Databricks): PostgreSQL storage, operation, and recovery of the server-side account, identity, consent, reading, private-note, community, transaction, and support data listed in section 1. Passwords are hashed and key personal data encrypted.
• Sendinblue SAS (Brevo): verification, recovery, and service emails; email address, message content, and delivery/receipt/error records. Marketing email requires separate consent.
• Google LLC (Firebase Cloud Messaging): push delivery; push tokens, installation identifiers, notification content, destination links, and delivery information. Service and marketing notifications are distinguished.
• NHN KCP Corporation: mobile identity verification, including PASS, temporarily processing name, telephone number, date of birth, carrier, gender, nationality classification, CI, and DI. Results stored by the Service are limited to section 1.

Support mail at [email protected] is received and stored through Google Gmail. Addresses, messages, and attachments sent there are processed through Google's email infrastructure. Do not send unnecessary identifiers or passwords. In-app and web support forms are also available.

Comments, replies, and reviews are filtered internally without sending their text to an external AI service. Reports are reviewed by internal filters and the operator. Entrusted processing is subject to legally required purpose restrictions, security, subprocessor management, deletion/return, and supervision.

5. Overseas transfers

Necessary outsourced processing/storage for contract performance is distinguished from independent processing by external providers. PIPA Article 28-8(1)(3) applies only to the former. Other disclosures/transfers require their own lawful basis, including separate consent where required. Transfers use encrypted communications when the relevant feature or server operation is used. Section 2 governs the Service's retention, without authorizing independent additional use by a processor.

Distributed processing countries and supplier log/recovery retention are not identical to the Service's single database region or retention periods. The Service must verify and disclose the relevant countries, data and periods; this notice alone does not authorize new optional transfers lacking required notice or consent. Transfer objections, suspension and deletion requests: [email protected] or +82-70-8064-3041.

For independent collection by Google login/Play and Apple login/App Store, also consult the providers' section 3 notices. The Service's verification requests may include authorization codes/tokens, product/transaction IDs, purchase/refund status and request IP. Google LLC is US-based. Apple Inc. is US-based and relevant account/store contracting entities also process information; Apple's Korean-service notice identifies Singapore-based Apple Services Pte. Ltd., among others. Avoiding a feature restricts that external login/payment feature, without eliminating statutory retention of transactions already made.

6. Deletion and backups

Information is destroyed promptly after retention expiry or purpose completion. Electronic data is erased in a manner preventing recovery; paper is shredded or incinerated. Scheduled deletion runs daily. Statutory and dispute records have restricted purposes and access and are not reused for normal service or marketing. A deleted account's internal ID remains personal information while linkable to retained records.

The Service's encrypted local database backups are kept only for recovery, for at most 30 days from creation. Supplier database recovery history has its own configured rotation and is not guaranteed to disappear simultaneously with deletion from the live database. Before restored backups return to service, subsequent deletion/correction requests are reapplied and expired data cleared.

7. Rights and requests

You may request access, correction, deletion, suspension of processing, withdrawal of consent, or account closure through app Account Management, https://eunhasu.info/account-deletion, or [email protected]. Optional marketing consent can be changed in Account Management. After verifying identity or legitimate representation, requests are handled within statutory periods. Refusing data essential to contract performance may prevent the associated account or feature from operating.

8. Automatic collection and advertising choices

The app keeps sessions, progress and settings in device storage. Restricted-content eligibility uses server-side KCP verification, not editable local values. The public website does not use behavioral-analytics cookies.

Google Mobile Ads SDK may process IP addresses, app interactions, diagnostics, Android advertising ID/App Set ID and other device identifiers for advertising, measurement and fraud prevention. Google UMP handles required regional choices before ads are enabled. From iOS 1.1.6 build 40, ATT is checked before the ad-consent process and ad requests. With permission, the ad provider may use IDFA for measurement. If denied or restricted, IDFA-based tracking is not performed and basic app functions remain available. Requests remain non-personalized; publisher first-party IDs and ad personalization are disabled. Google's regional ad/device-storage choices are separate from ATT and do not override an ATT denial. Change ATT under iOS Settings > Privacy & Security > Tracking. Earlier iOS builds do not request ATT or use IDFA for cross-app tracking.

Supported app versions record ad-privacy observations and changes/withdrawals: random installation ID, app/OS version, observation time, ATT status, CMP-provided choice signals and setting outcomes. IDFA, email and precise location are not added to this evidence. It never restores ad permission: the device's current OS/CMP state prevails. Where settings are required, choices may be changed or withdrawn in the app's advertising-privacy settings. Evidence is kept through account lifetime plus three years after deletion, then deleted. Cloudflare/Neon processing described above applies. Installation IDs/signals are personal information and the record alone does not prove every required legal consent. Banner and rewarded ads follow the same privacy-choice requirements.

9. Children and age verification

The Service is for users aged 14 or older and does not collect under-14 children's personal information without legal-representative consent. Registered users must complete KCP verification for age-15/19 restricted content. Date of birth determines age; DI, provider and time are encrypted. Verification is valid for one year. Name, phone number, CI, gender, carrier and nationality classification are temporarily processed and not stored; resident registration numbers are not collected. Users below the relevant age cannot access restricted content.

10. Security

We use Argon2id password hashing, encryption of key stored data, HTTPS/TLS, least-privilege administration, authentication/access controls, rate limits, duplicate and tampering checks for payments and ad rewards, keyed pseudonymous delivery fingerprints with restricted reverse lookup, security checks, backups and limited personnel access.

11. Privacy Officer

• Kyounghwan Jung
• Email: [email protected]
• Telephone: +82-70-8064-3041
• Address: Room 201, 30 Dorim-ro 20ga-gil, Guro-gu, Seoul, Republic of Korea

12. Remedies

• KISA Privacy Infringement Report Center: 118 / https://privacy.kisa.or.kr
• Personal Information Dispute Mediation Committee: 1833-6972 / https://www.kopico.go.kr
• Supreme Prosecutors' Office: 1301 / https://www.spo.go.kr
• Police cybercrime reporting: 182 / https://ecrm.police.go.kr

13. Changes

Changes are published in the app and website before taking effect. Material effects on rights normally receive 30 days' advance notice, with renewed consent where required. Previous policies: https://eunhasu.info/privacy-2026-08-24 and https://eunhasu.info/privacy-2026-07-20. This revision clarifies actual processing, retention and rights and improves deletion/refund protections. Publishing a policy does not replace separate consent required for new collection, disclosure or overseas transfer.

Business information

• Business/service: Eunhasu / Representative: Kyounghwan Jung
• Business Registration No.: 414-02-65870
• Mail-order Business Report No.: 2026-Seoul Guro-1242
• Business verification: https://www.ftc.go.kr/bizCommPop.do?wrkr_no=4140265870
• Address: Room 201, 30 Dorim-ro 20ga-gil, Guro-gu, Seoul, Republic of Korea
• Telephone: +82-70-8064-3041 / Email: [email protected]