Privacy Policy

Last updated: 6 September 2026

Learn Physics provides free-access physics notes, simulations and quizzes at learn.physicslens.com. This policy explains how the site handles information when you browse, sign in and save learning progress.

Google sign-in and account information

Signing in is optional. When you choose Google sign-in, Google authenticates you and shares basic account information with Firebase Authentication, including your Google account identifier, email address and, when available, your name and profile picture. Learn Physics uses your email address and Firebase user identifier to associate your account with your saved progress. The progress database does not copy your Google name or profile picture.

Learn Physics does not request access to your Gmail messages, Google Drive files, contacts or calendar. Google handles your Google password; Learn Physics does not receive it. If you choose email and password sign-in instead, Firebase Authentication handles those credentials and password reset emails.

Learning progress and storage

The site saves learning progress in your browser's local storage. Progress can include the learning page, completion status, quiz scores and attempt dates. When you sign in, the site syncs progress to Google Cloud Firestore and stores your email address, Firebase user identifier and update timestamps so you can access your progress across devices.

Firebase Authentication stores account information and manages sign-in sessions. Browser storage is also used to keep you signed in. Signing out does not by itself delete your account or saved progress.

How information is used and accessed

Account information is used to identify your account and provide progress storage and syncing. The site administrator can view learner email addresses and progress summaries through the administration interface. Google processes information through Firebase Authentication, Cloud Firestore, Firebase Hosting and Google Analytics to provide these services.

Your email address is not used for promotional activities or other commercial uses. Learn Physics does not sell your Google account information or learning progress.

Website analytics

The site uses Google Analytics, including Firebase Analytics, to measure website usage. These services may collect page views, interactions, browser and device information, and cookie or similar identifiers. Analytics collection is separate from saving your learning progress and may occur even when you are not signed in. For details about Google's processing, see Google's Privacy Policy.

Retention and your choices

Saved account and cloud progress records remain stored until they are deleted; the app does not automatically expire them. You can remove locally stored progress and session information by clearing this site's data in your browser. This does not delete cloud records, and signing in again can restore saved cloud progress.

To request deletion of your Learn Physics account and cloud progress, use the contact form and provide the email address used for your account. Account ownership may need to be confirmed before deletion.

You can also remove Learn Physics access through your Google Account connections. Removing access does not automatically delete information already stored by Learn Physics. You can continue to browse the learning materials without signing in.

Contact

For privacy questions or requests, contact Tan Seng Kwang using the contact form.

The contact form uses FormSubmit to process your email address, optional name, topic and message and forward them to the site administrator by email. These details are used to respond to your request. FormSubmit provides a spam check and retains submissions for 30 days. See FormSubmit's Privacy Policy for details about its handling of information.