Terms and Conditions

1Introduction

Vietgo (the “App”) is a free, offline app for learning Vietnamese. It bundles a dictionary, graded short stories, grammar guides, everyday phrases, a Sounds & Tones trainer and spaced-repetition tests, and it stores everything you create on your own device. There are no accounts, subscriptions, ads or in-app purchases.

The App is published by Ruminski Labs OÜ, a private limited company registered in Estonia, at Sepapaja tn 6, 15551 Tallinn, Estonia (“Ruminski Labs”, “Vietgo”, “we”, “us”, or “our”). You can reach us at contact@ruminskilabs.com.

These Terms and Conditions exist mainly to protect the App and its content licences. By using the App you agree to them, so please read them before diving in.

2Eligibility

Vietgo is suitable for users of all ages. You agree to comply with all applicable laws in your jurisdiction while using the App. If you are accessing the App from a region where its use is restricted, it is your responsibility to ensure compliance with local regulations.

3Licence to Use the App

We grant you a personal, non-exclusive, non-transferable licence to install and use the App on devices you own or control, for your own non-commercial language learning. The App is free of charge and every feature is available to every user; there is nothing to unlock.

Because the App is entirely local, you are responsible for your own data. Your word lists, favourites, progress and settings live only on your device and are removed if you uninstall the App or clear its storage. We have no copy and cannot restore them.

4Content Usage

Vietgo provides content designed to help you learn Vietnamese, including the offline dictionary, example sentences, short stories, grammar explanations and phrase collections. By using the App you agree to the following:

1. Personal Use Only. All content in the App is for your personal, non-commercial use. You may not use it for commercial purposes, mass distribution, or in any way that infringes the rights of Vietgo or third parties.
2. No Redistribution. You may not copy, extract, redistribute, reproduce or resell the App’s content, including the bundled dictionary database and story library, without prior written permission from Vietgo, except where a third-party licence listed in the App expressly allows it.
3. Third-Party Licences. The App incorporates openly licensed data from third-party sources. Those sources and their licences are listed under Settings › About › Data Sources & Licences in the App, and reproduced in full below, and their terms continue to apply to that data.
4. Feedback. Any feedback or suggestions you send us by email may be used by Vietgo to improve the App. By sending them you grant Vietgo a non-exclusive, royalty-free, perpetual licence to use them.
5. Educational Disclaimer. The stories, grammar notes and cultural explanations are for educational purposes only. We make every effort to keep them accurate, but we do not guarantee that every explanation, translation or pronunciation note is free of errors. All characters and events in the stories are fictional unless stated otherwise.

5Privacy

The App collects no personal data and makes no network requests. For details, please read our Privacy Policy.

6Intellectual Property

Vietgo and all materials within the App, including its design, features and branding (such as the name “Vietgo” and any associated logos), are the property of Ruminski Labs OÜ or licensed to it.

You agree not to:

• Use Vietgo’s name, branding or materials in a way that suggests endorsement or association without prior permission.
• Copy, modify or create derivative works from the App’s interface, features or content without authorisation.
• Reverse-engineer, decompile or attempt to extract the App’s source code, except as permitted by applicable law.

The inclusion of licensed third-party data does not grant you ownership or rights beyond those provided by the respective licences.

7Prohibited Activities

You agree not to:

1. Decompile, disassemble or reverse-engineer any part of the App, except as permitted by law.
2. Extract, scrape or bulk-export the bundled dictionary, stories, grammar or phrases for redistribution, except where a third-party licence listed above expressly allows it.
3. Distribute modified copies of the App or its content.
4. Use the App for any unlawful purpose or in violation of applicable laws or regulations.

Vietgo reserves the right to pursue legal remedies for violations of these Terms.

8Disclaimer of Warranties

Vietgo is provided on an “as is” and “as available” basis. While we strive to keep the App’s functionality and content accurate and reliable, we do not guarantee that it will be free from errors, interruptions or other issues, or that it will meet your specific needs.

Your learning outcomes depend on your own effort, consistency and engagement. Vietgo provides tools and resources to support your Vietnamese learning, but we cannot guarantee specific results.

To the fullest extent permitted by applicable law, Vietgo disclaims all warranties, whether express or implied, including implied warranties of merchantability, fitness for a particular purpose and non-infringement.

9Limitation of Liability

To the fullest extent permitted by applicable law, Vietgo, its developers and any affiliated parties shall not be liable for any direct, indirect, incidental, consequential or punitive damages arising out of your use of the App. This includes, but is not limited to:

• App Malfunctions: losses caused by technical issues, errors or interruptions in the App’s functionality.
• Data Loss: loss of word lists, progress or other locally saved data due to technical failures, device loss, uninstalling the App or clearing its storage.
• Learning Outcomes: dissatisfaction with your language learning progress or results.
• Third-Party Services: issues related to the app store you installed the App from, your device’s text-to-speech engine, or other apps the App hands off to (such as your mail or share apps).

As the App is free of charge, Vietgo’s total liability for any claim related to your use of it shall not exceed zero euros (EUR 0), except where applicable law does not permit such a limitation.

By using Vietgo you acknowledge that you do so at your own risk and agree that these limitations are reasonable.

10Changes to the Terms

We may update these Terms from time to time to reflect changes in the App or legal requirements. Updated Terms take effect when they ship inside an App update, with a new effective date on this page. By continuing to use Vietgo after an update, you agree to the revised Terms.

11Governing Law

These Terms are governed by and construed in accordance with the laws of Estonia, without regard to its conflict-of-law rules, and the courts of Estonia have jurisdiction over any disputes arising out of or in connection with them.

If you are a consumer, this does not deprive you of the protection of the mandatory consumer-protection rules of the country where you live, and you may also be able to bring proceedings in your local courts.

12Apple and Google Store Terms

You also agree to the applicable Apple App Store and Google Play terms. Where you obtained the App from the Apple App Store: these Terms are between you and Ruminski Labs OÜ only, not Apple, and Apple is not responsible for the App or its content. Apple has no obligation to provide maintenance or support for the App. Apple is not responsible for any product warranties or for addressing any claims relating to the App (including product-liability, legal/regulatory or intellectual-property claims). Apple and its subsidiaries are third-party beneficiaries of these Terms and may enforce them against you. You confirm that you are not located in a country subject to a U.S. Government embargo, and that you are not on any U.S. Government restricted-parties list.

13Contact Information

If you have any questions, concerns or feedback about these Terms, please contact us at contact@ruminskilabs.com, or write to Ruminski Labs OÜ, Sepapaja tn 6, 15551 Tallinn, Estonia.