Privacy Policy
Last updated: September 2026EngSandbox ("we," "our," or "us") is committed to protecting your privacy. This Privacy Policy explains how we collect, use, and safeguard your information when you visit our website.
Information We Collect
We collect minimal information to operate and improve our service:
- Usage Data: Pages visited, features used, and interaction data collected via Google Analytics.
- Local Progress Data: Your vocabulary practice history and scores are stored locally in your browser using IndexedDB / SQLite WASM. We never access this data.
- Ad Data: Google AdSense may collect data as described in their privacy policy.
How We Use Your Information
We use the collected information to:
- Provide and maintain our English practice platform
- Analyze usage patterns to improve user experience
- Display relevant advertisements via Google AdSense
- Detect and prevent technical issues
Advertising & Cookies (Google AdSense)
We use cookies and similar tracking technologies for analytics and advertising purposes. Google AdSense and Google Analytics use cookies — including the Google DoubleClick cookie — to serve relevant ads, measure performance, and analyze traffic. You can control cookie preferences through your browser settings at any time.
Third-party vendors, including Google, use cookies to serve ads based on your prior visits to this or other websites. Google's use of advertising cookies enables it and its partners to serve ads based on your visits to this site and/or other sites on the Internet. You may opt out of personalized advertising by visiting Google Ads Settings, or opt out of a third-party vendor's use of cookies for personalized advertising by visiting aboutads.info. You can also learn how Google uses data from our site at policies.google.com/technologies/ads.
If you prefer not to see personalized ads, you can disable ad personalization in your Google account or enable “Do Not Track” / cookie blocking in your browser. Non-personalized ads may still be shown using contextual information such as page content and time of day.
Third-Party Services
We use the following third-party services:
- Google AdSense — for displaying advertisements. See Google's Privacy Policy.
- Google Analytics — for understanding site usage. See Google's Privacy Policy.
Data Security
All communication with our site is encrypted via HTTPS. Your practice data remains stored locally in your browser and is never transmitted to our servers. We do not operate any backend servers that collect or store personal information.
Your Rights
Depending on your location, you may have the right to:
- Access information we hold about you
- Request deletion of your data
- Opt out of cookie-based tracking
- Withdraw consent at any time
Contact Us
If you have any questions about this Privacy Policy, please contact us.
Changes to This Policy
We may update this Privacy Policy from time to time. Changes will be posted on this page with an updated "Last updated" date.