Privacy Policy for TubeLingua
Effective date: 20 August 2026. Last updated: 14 September 2026. Operator: TubeLingua. Developer contact: dinghongzju@gmail.com. This page is public HTML on a domain we own. You do not need a Google account to read it. This policy belongs to the TubeLingua Chrome extension. It is not a template, example, or parent-company policy.
What this application is
TubeLingua is a Chrome extension. It overlays bilingual captions on YouTube, looks up words on the current sentence, loops one caption, and saves timestamped notes. Google authentication happens only inside the installed extension. This website does not present an authentication wall.
What Google user data this application accesses
Our application will access the data you have provided to us through Google, including your Google account email address, your Google display name, and your Google profile photo.
When you authenticate with Google inside the Chrome extension, TubeLingua accesses the following Google user data:
- Your Google account email (OAuth scope userinfo.email)
- Your Google display name and profile photo (OAuth scope userinfo.profile)
- Your stable Google user id (sub), which Google returns with those scopes
We may collect, or process on behalf of our customers, the following categories of personal data when you use or interact with our products and services: Google email, Google display name, Google profile photo, Google user id, study notes (word, sentence, video identifier, timestamp), and paid-plan entitlement status.
We do not access Gmail, Google Drive, Contacts, Calendar, Google browsing history, or YouTube account data. We do not request those scopes.
How this application uses Google user data
We will use your data to provide you with the services you requested, such as displaying the signed-in identity in the Chrome side panel, synchronizing study notes, and checking whether a free trial or paid plan is active.
We use Google user data only to provide or improve user-facing features of TubeLingua:
- Email, name, and photo: show which Google account is connected in the side panel
- Google user id (sub): identify your notes and whether a trial or paid plan is active
- Email: optional Stripe Checkout customer_email so Stripe can send a receipt; also to grant lifetime access if the address is on our allowlist
We will not sell your data to third parties, but we may share it with our partners who help us provide our services, as described in the sharing section below. We do not use Google user data for advertising, profiling, credit-worthiness, lending, creating databases for resale, or to develop, improve, or train non-personalized AI and/or ML models.
How this application stores Google user data
Email, name, photo, Google user id, notes, and plan status are stored on our Cloudflare Worker and D1 database so we can sync notes and check access. Google access tokens stay with Chrome Identity on your computer until you sign out.
We store your personal information for a period of time that is consistent with our business purposes. We will retain your personal information for the length of time needed to fulfill the purposes outlined in this privacy policy unless a longer retention period is required or permitted by law. When the data retention period expires for a given type of data, we will delete or destroy it.
With whom we share, transfer, or disclose Google user data
We do not transfer or disclose your information to third parties for purposes other than the ones provided.
We do not transfer or disclose Google user data to third parties except as needed to provide TubeLingua:
- Cloudflare acts as a processor and hosts the database on our instructions
- Stripe may receive your email at checkout so a receipt can be sent; card numbers never reach TubeLingua servers
- Translation providers receive caption text only. They do not receive your Google account, email, or photo
We do not sell Google user data to data brokers, information resellers, or advertisers. We do not transfer Google user data for targeted advertising, user advertisements, personalized advertisements, retargeted advertisements, interest-based advertisements, credit-worthiness, lending, or training generalized machine-learning or artificial intelligence models.
How we protect Google user data
Security procedures are in place to protect the confidentiality of your data. We use encryption to protect your information.
Traffic to our Cloudflare Worker uses HTTPS encryption in transit. Access to notes and entitlements requires a valid Google token from Chrome Identity. API keys you type for optional translation providers stay in chrome.storage.local on this computer and are not uploaded to TubeLingua servers. We use encryption in transit to protect your information between the extension, Google, Cloudflare, and Stripe.
Data retention and deletion
We store your personal information for a period of time that is consistent with our business purposes. We will retain your personal information for the length of time needed to fulfill the purposes outlined in this privacy policy unless a longer retention period is required or permitted by law. When the data retention period expires for a given type of data, we will delete or destroy it.
You may request for your data to be deleted by deleting notes in the extension Notes tab, or by emailing dinghongzju@gmail.com with the Google account to delete. After we receive a deletion request we remove the matching records from Cloudflare. Uninstalling the extension clears local settings and API keys; cloud notes remain until you delete them or email us. Sign-out revokes the Google token.
Other data
Caption text is sent only to the translation engine in use (YouTube timedtext, Google’s public translate API, or a provider whose key you supplied). The developer does not log caption text. Payments are processed by Stripe under Stripe’s privacy policy. This website has no ads and no analytics cookies.
Children
TubeLingua is not directed at children under 13. Do not use Google authentication in the extension if you cannot agree to this policy.
Limited Use
TubeLingua’s use of Google user data is limited to providing or improving user-facing features of the extension, as disclosed above, and complies with the Google API Services User Data Policy and the Chrome Web Store User Data Policy, including Limited Use requirements.
Contact
dinghongzju@gmail.com · https://tubelingua.liamding.com/app
Not affiliated with YouTube or Google. “YouTube” is a trademark of Google LLC.