Terms of Use

Last updated: June 10, 2026

These Terms of Use ("Terms") govern your use of the WordChain mobile application ("App", "Service"), developed and operated by WordChain ("we", "us", "our"). By downloading, installing, or using the App, you agree to be bound by these Terms. If you do not agree, please do not use the App.

1. Service Description

WordChain is an educational mobile application designed to help users learn English vocabulary through a unique "Tech Tree" (dependency chain) system. The App connects words to each other in a meaningful hierarchy — each word you master unlocks new, more advanced words whose definitions build upon what you've already learned.

1.1 Key Features

• Tech Tree Learning System: Words are organized in a dependency graph where mastering foundational words unlocks advanced vocabulary
• Spaced Repetition System (SRS): An intelligent review algorithm schedules reviews based on your forgetting curve to move words from short-term to long-term memory
• AI-Powered Sentence Builder: Write sentences using target words and receive real-time feedback from Google's Gemini AI, including grammar correction, usage guidance, and expansion challenges
• Story Reading Mode: Read stories composed of words you've learned to reinforce vocabulary in context
• Text-to-Speech Pronunciation: Listen to natural pronunciation of words
• Google Drive Backup: Optionally back up your progress to your personal Google Drive
• Detailed Statistics: Track daily, weekly, and monthly learning progress with visual charts

1.2 Service Tiers

Feature	Free	Premium
Daily word learning	Limited	Unlimited
Advertisements	Banner, interstitial & rewarded ads	Completely ad-free
AI Sentence Feedback	Limited daily uses	Unlimited
Premium Stories	Partial access	Full access
Advanced Statistics	Basic	Full analytics
Google Drive Backup	Manual only	Automatic weekly + manual
Priority Support	—	✓

2. Subscription & Payment

2.1 Premium Subscription

• Premium subscriptions are offered on monthly and yearly billing cycles
• Payment is charged to your Apple ID (iOS) or Google Play account (Android) upon purchase confirmation
• Subscriptions automatically renew unless cancelled at least 24 hours before the end of the current billing period
• Renewal charges are applied within 24 hours before the current period ends
• Subscription management and payment processing is handled entirely by RevenueCat in coordination with Apple/Google

2.2 Free Trial

If a free trial is offered, it begins when you subscribe and lasts for the specified duration. If you do not cancel before the trial ends, your subscription will automatically convert to a paid subscription at the listed price.

2.3 Cancelling Your Subscription

You may cancel your subscription at any time through your device settings:

• iOS: Settings → Apple ID → Subscriptions → WordChain → Cancel
• Android: Google Play Store → Subscriptions → WordChain → Cancel

Upon cancellation, you retain access to premium features until the end of your current billing period.

2.4 Refund Policy

Refund requests are handled by the respective platform:

• iOS: Request a refund through Apple's Report a Problem page
• Android: Request a refund through Google Play's refund process

We do not have the ability to process refunds directly, as all payments are managed by Apple and Google.

3. AI-Generated Content

3.1 How AI Is Used

When you use the Sentence Builder feature, your sentences are sent to Google's Gemini AI model (gemini-2.5-flash-lite) for evaluation. The AI provides:

• Grammar correctness assessment
• Target word usage validation
• Constructive feedback in Turkish
• Sentence expansion challenges
• Mentor-style guidance for questions asked in Turkish

3.2 AI Content Disclaimer

• AI-generated feedback is provided for educational purposes only and may contain errors or inaccuracies
• AI responses do not constitute professional language instruction or linguistic certification
• We do not guarantee the accuracy, completeness, or appropriateness of AI-generated content
• AI responses are cached locally on your device (up to 200 entries) and are not permanently stored on our servers
• The AI processes your input according to Google's Gemini API Terms

4. Acceptable Use

By using the App, you agree to the following rules:

• Use the App only for personal, non-commercial educational purposes
• Do not attempt to reverse engineer, decompile, or extract the source code of the App
• Do not attempt to circumvent the App's security measures, usage limits, or subscription validation
• Do not use the App to distribute malware, spam, or harmful content
• Do not manipulate the App's revenue model by using ad-blocking tools on the free tier
• Do not submit abusive, offensive, or harmful content through the AI Sentence Builder or feedback systems
• Do not create multiple accounts or use automated tools to manipulate learning statistics

5. Intellectual Property

The App and all its content — including but not limited to design, code, word database, dependency algorithms, Tech Tree structure, AI prompts, stories, audio files, and visual assets — are protected by copyright and intellectual property laws. All rights are reserved.

You may not copy, distribute, modify, create derivative works from, or commercially exploit any part of the App without our express written permission.

6. Google Drive Backup

If you choose to use the optional Google Drive backup feature:

• Your Google account credentials are used solely for authentication and backup purposes
• Your data is written exclusively to your personal Google Drive's appDataFolder — a private, app-specific folder that is not visible to other apps or in your regular Drive files
• Backup data is not shared with, transferred to, or accessed by any third party
• We request only the minimum required Google Drive scope (drive.appdata) and your email for authentication
• Premium users receive automatic weekly backups; free users can back up manually
• You can disconnect your Google account and delete backups at any time from within the App

7. Advertisements

The free tier of WordChain displays advertisements served through Google AdMob:

• Banner Ads: Displayed at the bottom of certain screens
• Interstitial Ads: Full-screen ads shown between activities (with a minimum 2-minute cooldown between displays)
• Rewarded Video Ads: Optional ads you can watch to earn temporary bonus allowances (extra daily words, additional AI uses, etc.)

All advertisements are removed entirely with a Premium subscription.

8. Notifications

WordChain sends local notifications (generated on your device, not from our servers) for:

• Review Reminders: When words are due for spaced repetition review, with escalating urgency based on overdue duration
• Daily Learning Prompts: Afternoon reminders to learn new words
• Streak Maintenance: Evening alerts if no learning activity has been recorded that day

You can disable all notifications through your device settings at any time. Disabling notifications does not affect any other app functionality.

9. Disclaimer of Warranties

• The App is provided "as is" and "as available" without warranties of any kind, whether express or implied
• Word definitions, translations, grammar explanations, and AI-generated feedback may contain errors
• The App does not replace professional language education, tutoring, or certification
• Features requiring an internet connection (backup, AI content, advertisements, content updates) may not function offline
• We are not responsible for data loss; regular backups via Google Drive are strongly recommended
• We do not guarantee uninterrupted, error-free, or secure operation of the App or its third-party integrations

10. Limitation of Liability

To the maximum extent permitted by applicable law, WordChain and its developer shall not be liable for any indirect, incidental, special, consequential, or punitive damages, including but not limited to:

• Loss of data, learning progress, or streak information
• Interruption of service or inability to access features
• Errors in AI-generated content or word data
• Unauthorized access to your data due to factors beyond our reasonable control
• Charges incurred due to failure to cancel a subscription

11. Account & Data Deletion

11.1 Deleting Local Data

You can delete all locally stored data by uninstalling the App from your device. This permanently removes all learning progress, word lists, statistics, and cached data stored in the Hive database.

11.2 Deleting Cloud Data

To request deletion of data stored on our servers (Firebase Analytics data, Firestore feedback records), please contact us at merisoftb1@gmail.com. We will process your request within 30 days.

11.3 Deleting Google Drive Backups

You can delete your Google Drive backup by signing out of Google within the App. Alternatively, you can manually delete the backup from your Google Drive's hidden app data. Disconnecting your Google account does not delete existing backups — you must explicitly request deletion.

12. Changes to These Terms

We may update these Terms of Use from time to time. When significant changes are made, we will notify you through an in-app notification. Continuing to use the App after changes are posted constitutes your acceptance of the updated Terms.

We recommend reviewing these Terms periodically. The "Last updated" date at the top of this page indicates when the Terms were last revised.

13. Governing Law & Dispute Resolution

These Terms are governed by and construed in accordance with the laws of the Republic of Turkey. Any disputes arising from or related to these Terms or your use of the App shall be subject to the exclusive jurisdiction of the courts of Turkey.

Before initiating any legal proceedings, we encourage you to contact us first to attempt to resolve the issue informally. Most concerns can be addressed promptly through email communication.

14. Severability

If any provision of these Terms is found to be unenforceable or invalid by a court of competent jurisdiction, that provision will be limited or eliminated to the minimum extent necessary, and the remaining provisions will remain in full force and effect.

15. Contact Us

For questions about these Terms of Use, feedback, or support: