Yi Folio LLC | yifolio.com | vocabfolio.app
Last Updated: September 3, 2026
Language: This Privacy Policy is originally written in English. In the event of any conflict between the English version and any translation, the English version shall prevail.
This Privacy Policy explains how Yi Folio LLC ("Company," "we," "us," or "our") collects, uses, stores, and protects your personal data when you use our corporate website (yifolio.com), our VocabFolio web application (vocabfolio.app), and our VocabFolio Android mobile application available on the Google Play Store (collectively, the "Service").
We are committed to protecting your privacy. We do not sell your personal data to third parties. Please read this policy carefully before using the Service.
When you register, we collect: your email address, full name, username (screen name), password (stored as a hashed value — never in plain text), native language, language code, and profile role (student or teacher). Age and gender are optional fields you may choose to provide. This information helps us better understand our learner community — it is not used to change your experience within the app, and is not required to register or use the Service. Your screen name is used to identify you within community features; do not use your real name if you prefer not to be publicly identified.
If you register through a third-party provider (such as Google, Microsoft, Facebook, or Apple, where available), we receive your name and email address as permitted by your privacy settings on that platform. We do not receive your password from these providers.
The core of VocabFolio is your personal vocabulary library. We store: words you add (headword, part of speech, IPA pronunciation, meanings, examples, forms, synonyms, antonyms), your custom notes and tags, word categories you create, AI-generated quiz sentences linked to your words, your Spaced Repetition System (SRS) data (mastery level and next review date per word), and your study session records (session type, date, duration in seconds, words studied, correct/incorrect answers, and XP earned). This data is private to you, except as described below for class/teacher features. If you use bulk import to add words (via CSV, Excel, TXT, PDF, or JSON file upload), the uploaded file itself is stored on our servers in addition to the extracted vocabulary data.
We store experience points (XP) earned through study activity, your current level, and any badges you have earned (including date earned and context). This data powers the gamification system within the application.
If you are a teacher using Premium features, we store: Classes you create (name, description, grade level, subject, join code), students you enroll (student name, student email if provided, student ID, enrollment date, teacher notes about the student (visible to the teacher only — not shared with or visible to students)), Quizzes you create (title, questions, difficulty, publication status), Assignments you create (linked quiz, due date, instructions), and Quiz Submissions made by your students (student name, email, grade level, class name, score, total questions, correct answers, and a full question-by-question answer breakdown). Student quiz data is visible only to the teacher who created the class and to the student who submitted it. Teacher notes are private to the teacher only and are never displayed to students.
Advanced and Premium users can share a chosen vocabulary list via a unique link ("SharedList"). The following data is processed in connection with this feature:
Important for Users: Because the share link grants public access (no login required), users should not include sensitive or personally identifiable information in any vocabulary list they intend to share. Users can revoke access at any time by deleting the SharedList from their account.
When you use AI-powered features, we send the minimum necessary data to our AI providers: your vocabulary term and native language for content generation; your chat query and limited account metadata (plan status, role, word count) for customer support. If your issue is escalated, this chat history is compiled into a Support Ticket accessible to our support staff, and we will email your registered address with status updates. We do not send your name, email, or sensitive personal data to AI providers for content generation. Our AI providers (including OpenAI and/or Anthropic) are contractually prohibited from using your submitted data to train their public models.
If you participate in the referral program, we store your unique referral code, the user ID of the person who referred you (if applicable), and user IDs of people who signed up using your code. This data is used solely to calculate and award referral bonuses and is not shared with third parties.
If you purchase a paid subscription, your payment information is collected and processed directly by Stripe, our PCI-certified payment processor. Yi Folio LLC does not store or access your full credit or debit card number. Authorized staff may access limited metadata within the Stripe Dashboard (last 4 digits, expiration date) solely to validate your identity for support requests.
If you voluntarily subscribe to our newsletter from yifolio.com, we collect your email address. This is separate from your VocabFolio app account and is used strictly to send relevant updates and promotional materials. You can unsubscribe at any time.
We collect standard, first-party usage data tied to your authenticated account: which pages and features you visit within the app, used to understand usage patterns and improve the Service. We also perform a one-time, in-memory lookup of your IP address, using a GeoIP database running entirely on our own infrastructure, to determine your general country/region for app functionality. Your IP address is not sent to any third party for this lookup, and the result is not persisted or stored. We do not use Google Analytics or third-party advertising trackers.
When you use the VocabFolio Android app (available on Google Play), we may collect the following additional data not applicable to the web version:
Android Notifications Note: If you use the VocabFolio Android app, you can enable or disable study reminders at any time in your device settings. We do not use your data for personalized advertising.
If you use the "Add Words from Photo" feature, the image you upload is sent to our third-party AI vision provider to extract vocabulary text from it. If you use speech-to-text ("Speech Input") or listen to word pronunciation (text-to-speech), your audio recording and/or the generated pronunciation audio is processed by our third-party AI provider (currently OpenAI's Whisper for transcription).
The extracted text (words, transcript) is saved to your account as described in Section 2.3. The original uploaded image or audio file is also retained in our cloud file storage — due to the same current platform storage limitation described in Section 6 for bulk-import files, these original files are not automatically deleted when you delete your account. We are working with our platform provider to add automated file deletion in a future update.
We do not use uploaded photos or audio for any purpose other than the feature you used them for. The same AI-provider protections described in Section 2.7 apply.
If you are located in the European Union or European Economic Area, we process your personal data on the following legal bases under GDPR Article 6:
We use your data to: operate and personalize the learning experience; generate AI-powered educational content; process payments; communicate with you about your account and billing; improve application stability and features; and operate the referral program.
We share data only with the following trusted service providers who are contractually bound to protect your data and to use it only for the purposes we specify:
If you join a class created by a teacher, your name, email, quiz scores, and answer history within that class will be visible to the teacher within the VocabFolio platform.
We may disclose your data when required by law, court order, or governmental authority, or where necessary to protect the rights, safety, or property of Yi Folio LLC or others.
Your personal data is processed and stored on servers operated by our service providers in the United States. For EU/EEA users, such transfers are safeguarded by Standard Contractual Clauses (SCCs) approved by the European Commission. For Taiwan users, we ensure appropriate safeguards are in place as required under the Taiwan Personal Data Protection Act.
We retain your data for as long as your account is active. When you delete your account, your personal data is deleted as follows:
VocabFolio supports 13 native languages, meaning our users come from countries across the world. Different jurisdictions have different data protection laws. The list below maps each major region to the applicable framework. Sections 7.2 and 7.3 below provide full details for the two highest-obligation frameworks (GDPR and Taiwan PDPA). For all other jurisdictions, Section 7.1 and Section 7.5 apply.
Regardless of where you are located, all VocabFolio users have the right to:
To exercise any of these rights, email contact@vocabfolio.app or hello@yifolio.com with the subject line "Data Rights Request" and your registered email address. We will acknowledge your request within 5 business days and respond fully within 30 days.
If you are located in the European Union or European Economic Area, you have the following additional rights under the General Data Protection Regulation (GDPR):
To exercise GDPR rights, email contact@vocabfolio.app or hello@yifolio.com. We will respond within 30 days as required by GDPR Article 12.
Yi Folio LLC is operated from Taiwan. Regardless of where our users are located, the Taiwan PDPA applies to our data processing operations. If you are a Taiwan resident, the following rights apply to you specifically under the PDPA:
Purpose of Collection: We collect personal data solely for providing educational services, processing payments, sending opted-in communications, and improving the application.
International Transfers: Your data is processed on servers in the United States. We ensure appropriate safeguards are in place for such transfers as required under the PDPA.
To exercise your Taiwan PDPA rights, email contact@vocabfolio.app or hello@yifolio.com with the subject line "PDPA Request." We will respond within 15 business days.
If you are a California resident, the California Consumer Privacy Act (CCPA) and California Privacy Rights Act (CPRA) give you the right to know what personal information we collect, request its deletion or correction, and opt out of its sale or sharing. Yi Folio LLC does not sell or share your personal information for cross-context behavioral advertising. To submit a CCPA request, email contact@vocabfolio.app or hello@yifolio.com with the subject line "CCPA Request." We will respond within 45 days as required by California law.
VocabFolio is a global product supporting learners in many countries. We recognize that users in Japan, South Korea, Brazil, Thailand, Indonesia, Vietnam, the Middle East, and elsewhere may have rights under their local data protection laws — including Japan's APPI, Korea's PIPA, Brazil's LGPD, Thailand's PDPA, and Indonesia's PDP Law, among others.
Regardless of your country, we extend the following commitment to all users worldwide:
As VocabFolio grows in specific markets, we will add jurisdiction-specific compliance notices to this policy where required by law.
To exercise any data right from any country: email contact@vocabfolio.app or hello@yifolio.com with the subject line "Data Rights Request — [Your Country]" and your registered email address. We will acknowledge within 5 business days and respond within 30 days.
In-App Deletion. Go to Settings → Danger Zone → Delete Account in the app. This permanently deletes your profile, vocabulary lists, study history, and all associated data. A confirmation email is sent to your registered address once deletion is complete.
Web-Based Deletion Request. If you can no longer sign in to the app, submit a deletion request via our public web form at https://app.vocabfolio.app/delete-account using your registered email. Our team verifies your identity and completes the deletion within 30 days. Android users: this complies with Google Play's account deletion requirement — both in-app and web paths are available.
Facebook Data Deletion. If you linked your account via Facebook Login: (1) Go to Facebook Account Settings & Privacy > Settings. (2) Click Apps and Websites. (3) Search for VocabFolio and click Remove.
By Email Request. Email contact@vocabfolio.app or hello@yifolio.com to request account deletion or exercise any data rights. We will confirm receipt and process your request within 30 days.
We implement appropriate technical and organizational measures to protect your personal data, including:
No method of electronic storage is 100% secure. While we implement commercially acceptable safeguards, we cannot guarantee absolute security.
In the event of a personal data breach that is likely to result in a risk to your rights and freedoms, we will:
Our Service is strictly not directed at children under the age of 13. We do not knowingly collect personal data from anyone under 13. Teachers or schools wishing to use VocabFolio with students under 13 are solely responsible for obtaining verifiable parental consent and complying with applicable student privacy laws (such as COPPA in the United States) before instructing students to create accounts.
If you believe a child under 13 has provided us with personal information, please contact contact@vocabfolio.app or hello@yifolio.com and we will promptly delete the account and all associated data.
We use essential cookies, local storage, and similar browser storage technologies to operate the Service — for example, to keep you signed in, remember your language and study preferences, and display the app correctly. We do not use a cookie consent banner because we do not deploy non-essential tracking or advertising cookies. You can clear or block cookies in your browser settings; some features may not function properly without them.
For registered users, we send strictly service-related emails: password resets, billing confirmations, subscription change notices, email verification, support ticket updates, account-deletion confirmations, and security alerts. You cannot opt out of these essential communications while your account is active.
If you have subscribed to our newsletter or opted in to product updates, we will periodically send promotional emails. You may opt out at any time by clicking "Unsubscribe" in any promotional email or by contacting contact@vocabfolio.app or hello@yifolio.com.
For corrections, clarifications, or non-material updates, we will update the "Last Updated" date and the change takes effect immediately. For material changes that significantly affect your data rights or how we use your data, we will notify you via email at least 15 days before the changes take effect. For EU users, where material changes require a new lawful basis, we will seek your explicit consent.
Your continued use of the Service after the effective date of material changes constitutes your acceptance of the updated Privacy Policy, unless applicable law requires explicit consent.
The following summarises the personal data collected when you use VocabFolio on Android. Full details of each data type are in Section 2 above.
All data listed above is encrypted in transit. No data is used for advertising.
Yi Folio LLC
Email: contact@vocabfolio.app | hello@yifolio.com
Websites: yifolio.com / vocabfolio.app
30 N. Gould St. Ste. N., Sheridan, WY 82801, United States