tovin Labs

Kotoba (コトバ) Privacy Policy

tovin Labs (“the Company”, “we”, “us”) has adopted this Privacy Policy in accordance with Article 30 of Korea’s Personal Information Protection Act (PIPA) and other applicable laws to protect the personal information of data subjects (“Users”) and to handle related concerns promptly and effectively. This Privacy Policy applies to the Japanese-language learning mobile application “Kotoba (コトバ)” (the “Service”) provided by the Company.


1. Person Responsible for Processing

The Company has designated the following person to oversee personal information processing for the Service and to handle matters relating to data subject rights and remedies.


2. Categories of Personal Information We Collect

The Company collects only the minimum personal information necessary to provide the Service. We do not collect information that is not specified in this section.

2.1 Information Collected at Sign-Up and Sign-In

Authentication MethodItems Collected
Email / PasswordEmail address, password (hashed value), display name (optional)
Sign in with Google (OAuth 2.0)Email address, Google account identifier (sub), display name
Sign in with AppleEmail address (or the anonymous relay address issued by Apple’s “Hide My Email” feature), Apple user identifier, display name (collected only on first sign-in)

We never store passwords in plaintext; passwords are kept only as one-way hashes generated by Supabase Auth. If a User signs in with Apple and uses the “Hide My Email” feature, we receive and store only the anonymous relay address Apple issues (@privaterelay.appleid.com); we do not learn the User’s actual email address.

2.2 Information Collected Automatically Through Use of the Service

2.3 Information Processed When Using AI Features

When a User uses our AI tutor, grammar correction, study plan generation, or example sentence generation features, the following information is processed:

The Company does not transmit any directly identifying information — such as email addresses, names, or OAuth identifiers — to its AI processor (Anthropic, PBC).

2.4 Data Stored Locally on the Device (AsyncStorage)

The Service stores the following data only in the device’s local storage (AsyncStorage). This data is not transmitted to our servers and is removed when the app is uninstalled.

KeyPurpose
ai_chat_messagesUp to 30 most recent AI chat messages (temporary on-device cache)
ai_chat_levelThe User’s selected AI chat difficulty
ai_study_planCache of the AI-generated study plan
jlpt_target_dateThe User’s chosen JLPT target exam date
target_jlpt_levelThe User’s chosen target JLPT level
saved_emailEmail used to auto-fill the sign-in screen (only if the User opts in)
ADMIN_AUTH_KEYAdministrator-only authentication key (not used by regular Users)

2.5 Information We Do Not Collect

The Company does not collect any of the following information:


3. Purposes of Collection and Use

The Company uses the personal information it collects only for the purposes set out below. If we ever change these purposes, we will obtain separate consent or take other measures as required by Article 18 of Korea’s Personal Information Protection Act (PIPA).

Items CollectedPurpose of Use
Email address, OAuth identifier, display nameAccount identification, sign-in, identity verification, responding to inquiries
Learning activity logs, daily usage countersDisplaying learning progress, providing statistics, managing free and paid usage limits
Subscription expiry dateVerifying entitlement to paid features
Coin transactions, items, achievements, etc.Providing gamification features
AI input text, learning statistics summaryGenerating AI responses through the Anthropic Claude API
Customer support tickets, word reportsResponding to inquiries and improving content quality

4. Retention and Use Periods

As a general rule, the Company retains and uses a User’s personal information from the date of sign-up until the User withdraws membership. When a User requests withdrawal, information is handled as follows.

CategoryRetention Period
Account information (email, OAuth identifier, display name)Deleted immediately upon withdrawal (kept in segregated storage where Section 4.1 requires statutory retention)
Learning records (sessions, vocabulary statistics, coin transactions, etc.)Same as account information
AI input text (server side)Discarded immediately after processing. Edge Function ai-proxy may briefly retain it in logs for debugging purposes; such logs are automatically deleted within 30 days
AI input text (Anthropic side)Subject to the policies of Anthropic, PBC (see Section 5 below)
On-device AsyncStorage dataUntil the User uninstalls the app or clears the data manually

4.1 Statutory Retention Obligations

Where laws such as Korea’s Act on Consumer Protection in Electronic Commerce impose retention obligations, the Company retains the following items in segregated storage for the periods indicated.

Item RetainedRetention PeriodLegal Basis
Records of contracts or withdrawal of subscription5 yearsArticle 6 of the Enforcement Decree of the Act on Consumer Protection in Electronic Commerce (Korea)
Records of payment and supply of goods or services5 yearsArticle 6 of the Enforcement Decree of the Act on Consumer Protection in Electronic Commerce (Korea)
Records of consumer complaints or dispute resolution3 yearsArticle 6 of the Enforcement Decree of the Act on Consumer Protection in Electronic Commerce (Korea)

Account information beyond the items above is deleted immediately upon withdrawal.


5. Disclosure to Third Parties

The Company does not disclose Users’ personal information to third parties, except in the following cases:

  1. Where the User has given prior, separate consent
  2. Where required or permitted by applicable law, or in response to a lawful request from a law enforcement authority

6. Outsourced Processing (Sub-processors)

To provide the Service smoothly, the Company entrusts certain personal information processing tasks to the following sub-processors.

Sub-processorOutsourced TaskItems ProcessedRetention / Use Period
Supabase, Inc. (US company; data hosting region: AWS Tokyo, ap-northeast-1)User authentication, database hosting, Edge Function executionAll items listed in Sections 2.1, 2.2, and 2.3 of this Privacy PolicyUntil the User withdraws or the processing agreement ends
Anthropic, PBC (United States)Generating AI responses via Claude models (claude-haiku-4-5, claude-sonnet-4-6)Text submitted by the User to AI features, learning statistics summary (no email, name, or other identifiers are included)Discarded immediately after processing as a rule. Anthropic may retain data short-term under its own policies (e.g., for abuse prevention)

Google LLC (Sign in with Google) and Apple Inc. (Sign in with Apple) act as Identity Providers with whom the User authenticates directly upon their own consent; they are not sub-processors engaged by the Company. Their handling of personal information is governed by their respective privacy policies.

When entering into outsourcing agreements, the Company specifies — in writing, in line with Article 26 of Korea’s Personal Information Protection Act (PIPA) — that personal information may not be processed for any purpose other than the outsourced task, along with technical and managerial safeguards, restrictions on sub-outsourcing, supervision of sub-processors, and liability for damages. The Company supervises whether sub-processors handle personal information securely.


7. International Data Transfers

In accordance with Article 28-8 of Korea’s Personal Information Protection Act (PIPA), the Company transfers personal information overseas as set out below. By agreeing to this Privacy Policy at sign-up, the User is deemed to consent to these international transfers.

RecipientCountryDate and Method of TransferItems TransferredRetention / Use Period
Supabase, Inc.Japan (AWS Tokyo region, data storage) / United States (administrative and operational access)At sign-up and during use of the Service, transmitted over HTTPS (TLS 1.2 or higher)Items in Sections 2.1, 2.2, and 2.3Until the User withdraws or the processing agreement ends
Anthropic, PBCUnited StatesAt the time the User invokes an AI feature, transmitted over HTTPS via the Supabase Edge Function ai-proxyAI feature input text, learning statistics summaryPer Section 4 above and Anthropic’s own policies

Recipient contacts:


8. User Rights and How to Exercise Them

Users may exercise the following rights with respect to the Company under Articles 35 through 37 of Korea’s Personal Information Protection Act (PIPA):

  1. The right to request access to their personal information
  2. The right to request correction or deletion of their personal information
  3. The right to request suspension of processing
  4. The right to data portability (download)

Rights may be exercised by either of the following methods:

This Service is intended for users aged 14 or over. We confirm that the User is at least 14 years old at sign-up. If we discover that a User under 14 has registered, we will delete that account without delay. For children under 14, a legal representative may exercise the rights above on the child’s behalf, and we will respond to any such request — whether from the User or from a legal representative — without delay.

8.1 Additional Rights for EEA and UK Residents (GDPR Supplement)

If you reside in the European Economic Area (EEA), the United Kingdom, or Switzerland, you have the following additional rights under the GDPR and equivalent laws:

The legal bases on which we process your personal data are: (i) performance of the service contract (Article 6(1)(b) GDPR), (ii) your consent (Article 6(1)(a) GDPR), and (iii) our legitimate interests (Article 6(1)(f) GDPR). For transfers to the United States and Japan, we rely on Standard Contractual Clauses (SCCs) or equivalent safeguards.


9. Procedures and Methods for Destroying Personal Information

When personal information is no longer needed — for example, because the retention period has expired or the purpose of processing has been achieved — the Company destroys it without delay.


10. Automatic Data Collection: Operation and Opt-Out

Because the Service is a mobile application, it does not use web browser cookies. To provide the Service, however, we store the items listed in Section 2.4 of this Privacy Policy in the device’s local storage (AsyncStorage). You can remove this data at any time by clearing the app’s data through your device’s operating system or by uninstalling the app.


11. Security Safeguards

In accordance with Article 29 of Korea’s Personal Information Protection Act (PIPA), the Company implements the following technical, managerial, and physical safeguards.


12. Data Protection Officer and Department

The Company has designated the following Data Protection Officer (DPO) to oversee personal information processing and to handle data subject rights and remedies.

You may contact the DPO with any inquiry, complaint, or remedy request relating to personal information that arises during your use of the Service. We will respond to and act on your inquiry without undue delay.


13. Remedies for Infringement of Rights

If you wish to seek remedies for an infringement of your personal information rights, you may apply to the following Korean bodies for dispute resolution or consultation. These are independent of the Company; please contact them if you are not satisfied with the Company’s handling of a complaint or remedy request, or if you would like more detailed assistance.

In addition, anyone whose rights or interests have been harmed by an action or omission of the head of a public institution in connection with a request made under Article 35 (access), Article 36 (correction or deletion), or Article 37 (suspension of processing, etc.) of Korea’s Personal Information Protection Act (PIPA) may file an administrative appeal in accordance with Korea’s Administrative Appeals Act.


14. Notice of Changes

If this Privacy Policy is amended — by addition, deletion, or modification — we will give notice in the app or on tovinlabs.com at least 7 days before the changes take effect. For changes that materially affect User rights, we will give notice at least 30 days in advance and may, where necessary, request fresh consent.