Privacy Policy
Last Updated: 2025-03-27
Introduction
DejaVocab ("we", "our", or "the service") respects your privacy and is committed to protecting the personal information you provide when using our website (dejavocab.com), mobile applications (iOS and Android), and Chrome extension. This Privacy Policy is intended to inform you about the types of information we may collect and how we use this information.
Information Collection
Information We Collect
When you use DejaVocab services, we may collect the following types of information:
- Account Information: When you register an account, we collect your username, email address, and password (stored encrypted).
- Learning Data:
- Words you save and their definitions
- Video sentences you mark and their translations
- Videos you save and their metadata (URL, title, platform info)
- Video subtitles and timestamps
- Phrases you learn and their context
- Grammar analysis results
- Documents you read (PDF, EPUB) and reading progress
- Podcast listening records and subtitles
- Locally imported video and audio file information
- Session Data:
- Login session information (start and end times)
- Activity records during the session
- Chat session content and related settings
- Usage Data: We record your activities on the platform, such as:
- Login and logout times
- Video viewing records
- Subtitle saving operations
- Word lookup records
- Sentence adding activities
- Extension usage
- Podcast listening records
- Document reading progress
- Phrase learning records
- Credit usage
- Device Information:
- IP address
- Browser type and version
- Operating system
- Device type (desktop, mobile, or tablet)
- Usage Metrics: To improve our service, we track:
- Login count
- Number of saved videos
- Number of favorited words
- Number of saved sentences
- Number of phrases learned
- Number of documents read
- Last active time
- Credit usage statistics
- Subscription and Payment Information:
- Subscription type (Free, Premium, Ultra, Lifetime)
- Apple App Store or Google Play transaction information
- Subscription start and expiration dates
- Credit allocation and usage records
- Lifetime member number (if applicable)
- User Source Survey:
- How you learned about DejaVocab (e.g., Xiaohongshu, Bilibili, friend referral)
- Your learning goals
Information Collected by Mobile Apps
Our iOS and Android apps collect the following information:
- Words and sentences you select from YouTube and Bilibili videos
- Podcasts you listen to and their subtitles
- EPUB/PDF documents you read and reading progress
- Local video and audio files you import
- Video/audio subtitle content and timestamps
- Your app settings and preferences
- Subscription status and credit usage
- Device information (for cross-device sync)
Information Collected by Chrome Extension
Our Chrome extension collects the following information:
- Words and sentences you select from YouTube videos
- Metadata of videos you are watching (title, URL, platform type)
- Video subtitle content and timestamps
- Your extension settings and configuration
- Activity records during extension usage
Our apps and extensions will NOT:
- Monitor or collect all websites you visit
- Read or collect your browsing history
- Access or collect data without your authorization
- Share your personal data with unrelated third parties
- Access other files on your device (except content you actively import)
Information Use
We use the information we collect to:
- Provide Core Features:
- Store and manage your learning materials (videos, subtitles, words, sentences, phrases)
- Provide word definitions and translation services
- Support video, podcast, and document learning and review features
- Provide AI grammar analysis and learning suggestions
- Sync learning progress across devices
- Personalize Your Experience:
- Provide relevant recommendations based on your learning history
- Save your learning progress and preference settings
- Optimize content presentation
- Adjust learning content based on vocabulary level
- Recommend channels and podcasts suited to you
- Improve Our Services:
- Analyze feature usage patterns to identify improvement opportunities
- Diagnose technical issues
- Develop new features
- Provide User Support: Answer questions and resolve issues
- Ensure Security: Prevent fraud and abuse
- Generate Aggregate Statistics: Understand overall usage (without personally identifiable information)
Information Sharing
We do not sell, rent, or trade your personal information to third parties. We may share your information in the following circumstances:
- Service Providers: We may share information with trusted third-party service providers who help us operate our services (such as hosting providers or analytics providers).
- Payment Processing: Subscription payments are processed through Apple App Store or Google Play; we do not directly store your payment card information.
- AI Services: To provide translation, grammar analysis, and other features, your text content may be sent to AI service providers (such as OpenAI, Google) for processing.
- Legal Requirements: We may disclose your information if required by law or to protect our rights.
- With Your Consent: With your explicit consent, we may share your personal information with third parties.
Data Security
We take reasonable technical and organizational measures to protect your personal information from unauthorized access, use, or disclosure. These measures include data encryption, secure access controls, and regular security assessments. However, please note that no method of transmission over the Internet or electronic storage is 100% secure.
Your Rights
Depending on the data protection laws applicable in your region, you may have the following rights:
- Access your personal information
- Correct inaccurate information
- Delete your personal information
- Restrict or object to processing of your personal information
- Data portability
To exercise these rights, please contact us through the following contact information.
Cookie Usage
We use cookies and similar technologies to improve user experience, remember your preferences, and analyze website usage. You can control the use of cookies through your browser settings.
Children's Privacy
Our services are not intended for children under 13 years of age. We do not knowingly collect personal information from children under 13. If you are a parent or guardian and believe that your child has provided us with personal information, please contact us and we will take steps to remove such information from our systems.
Privacy Policy Updates
We may update this Privacy Policy from time to time. We will notify you of any changes by posting the new version on our website. We recommend that you review this page periodically for the latest information. Your continued use of our services will be deemed as acceptance of any modified Privacy Policy.
Contact Us
If you have any questions or comments about this Privacy Policy, please contact us through:
Email: postmaster@dejavocab.com
Terms of Service
Last Updated: 2026-03-03
1. Acceptance of Terms
Welcome to DejaVocab! By using our services, you agree to the following terms. If you do not agree to these terms, please do not use our services.
DejaVocab is an intelligent multimedia learning assistant that helps users learn languages through videos, podcasts, documents, and other content. We provide subtitle extraction, AI translation, phrase learning, grammar analysis, EPUB reader, and other features. You can use our services through our website, iOS app, Android app, or Chrome extension.
2. User Account
To use DejaVocab services, you must comply with the following account rules:
- Age Requirement: You must be at least 13 years old to use this service
- Account Security: You are responsible for protecting your account security and password confidentiality
- Information Accuracy: You agree to provide accurate and complete registration information
- Account Ownership: You may not transfer your account to others
- Anomaly Reporting: Please notify us immediately if you discover unauthorized use
3. Subscription Services
DejaVocab offers the following subscription plans:
Free Tier
- Basic feature access
- 50 credits per month
- Video subtitle extraction and translation
- Basic vocabulary learning
Premium
- 500 credits per month
- All premium features
- Deja Memory feature (phrase learning)
- Podcast subtitle generation
- EPUB/PDF document reading
- AI grammar analysis
- Monthly or yearly billing options
Ultra
- 1000 credits per month
- All ultra features
- Local video/audio import
- Quick transcription feature
- Priority support
- Monthly or yearly billing options
Co-Builder (Lifetime)
- Permanent access
- Credits accumulate monthly (Premium +500/month, Ultra +1000/month)
- Exclusive lifetime member number (e.g., #0001)
- Priority access to new features
- All Ultra features
4. Payment and Refunds
- Payment Channels: Subscription fees are processed through Google Play or Apple App Store
- Auto-Renewal: Subscriptions will auto-renew unless cancelled before the end of the current period
- Refund Policy: Refund policies follow the respective app store regulations
- Lifetime Membership: Lifetime membership is a one-time purchase and is non-refundable
- Price Differences: Prices may vary by region
5. Content Usage
- Content Ownership: You retain ownership of learning content created through the service (words, sentences, phrases, notes, etc.)
- Personal Use: Video subtitles, podcast transcriptions, and translations are for personal learning use only
- No Commercial Use: Commercial use or content distribution is prohibited
- Third-Party Content: We are not responsible for the accuracy of third-party videos, podcasts, or document content
- Copyright Compliance: Users must comply with relevant copyright laws
- Local Files: Local videos/audio/documents you import must be content you have the right to use
6. Prohibited Actions
When using this service, you agree not to:
- Violate any laws or regulations
- Infringe on others' intellectual property rights
- Distribute malware or harmful content
- Attempt unauthorized access to systems
- Abuse APIs or automation tools
- Interfere with normal service operation
- Create fake or fraudulent accounts
- Share, resell, or transfer your subscription
7. Service Changes
We reserve the following rights:
- Service Adjustment: Modify or terminate any part of the service
- Terms Update: Update these terms (major changes will be notified in advance)
- Price Adjustment: Adjust pricing (does not affect existing subscription periods)
- Account Handling: Restrict or terminate access for violating accounts
8. Disclaimer
- The service is provided "as is" without any express or implied warranties
- We do not guarantee uninterrupted or error-free service
- We are not liable for any damages arising from use of the service
- AI translation, grammar analysis, and phrase extraction may contain errors and are for reference only
- Subtitle transcription accuracy is affected by audio quality and language complexity
- You assume all risks associated with using this service
9. Intellectual Property
- Our Rights: DejaVocab's name, logo, software, and all related content are our intellectual property
- Your Rights: You retain ownership of learning content you create
- License Grant: We grant you a limited, non-exclusive, non-transferable license to use our services
- Prohibited: Unauthorized copying, modification, distribution, or reverse engineering of our software is prohibited
10. Privacy Protection
Your privacy is important to us. For information on how we collect, use, and protect your information, please see our Privacy Policy.
We commit to:
- Not selling your personal data
- Using industry-standard security measures
- Only collecting data when necessary
11. Dispute Resolution
- Applicable Law: These terms are governed by the laws of the People's Republic of China
- Dispute Resolution: Any disputes shall first be resolved through friendly negotiation
- Arbitration: If negotiation fails, disputes shall be submitted to the competent People's Court
12. Contact Us
If you have any questions or comments about these Terms of Service, please contact us through:
Email: postmaster@dejavocab.com
Website: https://dejavocab.com
Data Deletion Request
Last Updated: 2026-03-03
About Data Deletion
If you wish to delete your personal data in the DejaVocab app, we provide the following options. We respect your privacy rights and are committed to making the data deletion process simple and transparent.
Method 1: In-App Deletion (Recommended)
You can delete learning data directly in the DejaVocab app:
- Delete saved words: Go to word list → Swipe left to delete
- Delete saved phrases: Go to phrase list → Swipe left to delete
- Delete saved sentences: Go to sentence list → Swipe left to delete
- Delete video records: Go to video history → Delete records
- Delete documents: Go to document list → Swipe left to delete
- Clear cache: Settings → Cache Management → Clear Cache
⚡ Advantage: These operations take effect immediately, no review required
Method 2: Complete Account Deletion
If you wish to delete your entire account and all related data:
- Send an email to: postmaster@dejavocab.com
- Email subject: Data Deletion Request - DejaVocab
- Include your username or registered email
- State the reason for deletion (optional)
Data to be Deleted
After account deletion, the following data will be permanently deleted:
- Personal account information (username, email, password)
- All learning data (words, phrases, sentence collections)
- Video watch history and learning progress
- Documents and reading progress
- Podcast listening records
- Subscription and quota information
- App settings and preferences
Data Retained
Due to legal requirements or technical reasons, the following data may be retained:
- Anonymized usage statistics (without personally identifiable information)
- Necessary financial records (retained per tax and accounting regulations)
- Security logs (to prevent fraud and abuse)
⚠️ Important Notice
Account deletion cannot be undone
Please make sure you have backed up important learning data. If you are a paid user, account deletion will not automatically refund, please cancel your subscription first.
Processing Time
Immediate
7 business days
Up to 30 days
Contact Us
If you have any questions about data deletion, please contact us:
📧 Email: postmaster@dejavocab.com
🌐 Website: https://dejavocab.com
