By downloading, installing, or using the Grammar Studio mobile application (herein referred to as the "Application") for iOS devices, these Terms & Conditions will automatically apply to you. Please read them carefully before using the Application.

The Application is created and owned by Phi Van Son (herein referred to as the "Developer").

1. License to Use

The Developer grants you a personal, limited, non-exclusive, non-transferable, revocable license to install and use the Application on compatible Apple iOS devices owned or controlled by you, strictly for personal educational purposes in accordance with these Terms.

2. Free Tier & Premium Subscriptions

Grammar Studio offers both a Free Tier and optional Premium Subscriptions:

• Free Tier: Includes access to placement testing, structured syllabus lessons, daily challenges, bookmarking, and mistake review with non-intrusive advertisements.
• Premium Subscriptions: Available in Weekly, Monthly, and Annual subscription plans. Subscribing unlocks:
  • Personalized Weekly Focus Plan (3 adaptive sessions tailored to recent mistakes and CEFR level).
  • Advanced 30-Day Learning Analytics & accuracy consistency charts.
  • Unlimited Custom Practice (filter by specific CEFR level, skill group, and quiz length).
  • Progress Export (download your complete quiz history as CSV).
  • 100% Ad-Free environment.

3. Subscription Payment, Renewal & Cancellation

Premium payments are processed by Apple through StoreKit APIs and charged to your Apple ID account at confirmation of purchase.

• Subscriptions automatically renew unless auto-renew is turned off at least 24 hours before the end of the current billing period.
• Your Apple ID account will be charged for renewal within 24 hours prior to the end of the current period at the rate of the selected plan.
• You can manage or cancel your subscriptions anytime by going to your iOS Device Settings > Apple ID > Subscriptions.
• If you change devices or reinstall the app, you can restore active purchases anytime via Settings > Restore purchases inside Grammar Studio.

4. Intellectual Property Rights

All copyright, trademarks, database rights, design assets, exercise question datasets (including over 5,600 questions across 560+ core topics), explanations, animations, and source code belong exclusively to the Developer. You agree not to copy, reverse engineer, extract database files, or redistribute the Application content without explicit written consent.

5. Disclaimer & Limitation of Liability

The Application is provided on an "AS IS" and "AS AVAILABLE" basis. While we strive to maintain high pedagogical standards and accuracy, the Developer does not warrant that all exercises, answers, and explanations are completely error-free or uninterrupted.

6. Canonical Published Location & Contact

The canonical published version of these Terms is available at https://english-grammar-landing.vercel.app/terms.html.

If you have any questions regarding these Terms & Conditions, please contact us at:

Support Email: pvsasoftware@gmail.com