linguaflow-privacy

Privacy Policy for LinguaFlow

Last updated: 2 August 2026

LinguaFlow (“the app”) is a Mandarin Chinese learning app that turns videos you already own into interactive lessons. This policy explains exactly what the app collects, what it does not, and what control you have.

The short version: your videos, audio and transcripts never leave your device. The only things that reach a server are your account email (if you choose to sign in), a single sentence at a time when you explicitly ask for an AI explanation, and your subscription status.


Who we are

LinguaFlow is developed by I Nyoman Surya Pradipta.

Contact: suryapradipta@icloud.com

We are the data controller for the limited personal data described below.


What stays on your device

The core of LinguaFlow runs entirely offline. The following never leave your device and are never uploaded to us or anyone else:

Deleting the app deletes all of this permanently.


What we collect

1. Account information — only if you sign in

LinguaFlow can be used without an account in guest mode. If you choose to use Sign in with Apple, we receive:

We use this only to identify your account, apply your subscription, and enforce the free tier’s daily AI limit. We never use it for advertising and never sell it.

Authentication and account storage are handled by Supabase (Supabase Inc.), acting as our data processor.

2. Text you explicitly send to AI features

When you tap Explain on a subtitle line, or request pronunciation feedback, the app sends to our server:

That text is forwarded to OpenAI to generate the explanation, and the result is cached on your device so repeat views cost nothing.

This only happens when you actively tap an AI feature. No audio is sent — only text. Video, audio files and full transcripts are never sent.

OpenAI processes this data as our provider under their API terms and, per those terms, does not use it to train their models.

3. Subscription status

If you subscribe to LinguaFlow Pro, Apple processes the payment. We never see your payment details. We receive and store only the transaction identifier and whether your subscription is active, so the app can unlock Pro features across your devices.

4. Feedback you send us

If you use Send Feedback, your email app opens with a prefilled message containing your app version, iOS version and device model. You can edit or remove any of it before sending. We receive whatever you choose to send.


What we do NOT do


Permissions the app asks for

Permission Why Optional?
Microphone Recording your voice for shadowing practice and pronunciation scoring Yes — only needed for Practice
Speech Recognition Transcribing video audio and scoring pronunciation Yes — needed to process videos
Photo library Only the specific video you choose to import Yes — you can import from Files instead

A note on speech recognition

LinguaFlow uses on-device speech recognition by default. If the on-device Chinese model is unavailable, the app will ask for your explicit permission before sending audio to Apple’s servers for transcription. This never happens silently, and you can turn it off at any time under Me → Server Speech Recognition. Any such processing is covered by Apple’s Privacy Policy.


Children’s privacy

LinguaFlow is not directed at children under 13, and we do not knowingly collect personal data from them. If you believe a child has provided us personal data, contact us and we will delete it.


Your rights and choices

If you are in the EEA or UK, you have rights under GDPR to access, correct, export, restrict or erase your data, and to object to processing. If you are in California, you have rights under CCPA/CPRA — note that we do not sell personal information. Email us to exercise any of these; we respond within 30 days.

Our legal basis for processing under GDPR is performance of a contract (providing the app’s features you request) and consent (optional features such as server-based speech recognition).


Data retention

International transfers

Our processors (Supabase, OpenAI) may process data on servers outside your country, including in the United States, under appropriate safeguards such as Standard Contractual Clauses.

Third-party processors

Processor Purpose Policy
Supabase Inc. Authentication, account storage, backend functions https://supabase.com/privacy
OpenAI, L.L.C. Generating AI explanations and pronunciation feedback https://openai.com/policies/privacy-policy
Apple Inc. App distribution, subscriptions, optional server speech recognition https://www.apple.com/legal/privacy/

Security

Data in transit is encrypted with TLS. Backend access is protected by authenticated requests and row-level security, so one account cannot read another’s data. AI provider keys are held server-side and never shipped in the app.

Changes to this policy

If we make material changes we will update the date at the top of this page and note the change in the app’s release notes.

Contact

Questions about this policy or your data:

suryapradipta@icloud.com