Privacy Policy

Last updated: February 25, 2026

Lingle ("we," "our," or "us") respects your privacy. This Privacy Policy explains what information the Lingle iOS app collects and processes, how and why that information is used, when it is shared, and your choices and controls.

1) Scope

This Privacy Policy applies to the Lingle iOS application and related services.

2) Data We Collect and How We Collect It

A. Data You Provide Directly in the App

We collect data you choose to enter, including:

  • Email address (linked to your account/profile)
  • Profile details (such as first and last name)
  • Optional profile photo selected from your device
  • Learning content you enter, including:
    • journal entries (saved and linked to your account/profile)
    • translation responses
    • quiz answers and written exercises

B. Learning and Progress Data Generated by App Use

As you use learning features, the app records learning-related state, including:

  • language preferences
  • levels, XP, streaks, and challenge completion
  • saved vocabulary and saved articles
  • tutorial completion status

C. Data from Device Permissions (Optional)

We access these device features only if you grant permission in iOS:

  • Photos access (only if you choose to upload a profile image)
  • Notifications (only if you enable reminders)

D. Technical and Network Data Collected Automatically

When the app communicates with our services or third-party services, standard technical data may be transmitted, such as IP address, device type, app version, timestamps, and request metadata.

3) How We Use Information

We use collected and processed data to:

  • operate core learning features
  • identify and manage your account/profile
  • generate journal feedback and translation validation only when you submit content for analysis
  • create AI-based exercises and benchmarking results
  • store and restore your progress
  • improve reliability and performance of the app
  • send reminder notifications when enabled

Journal entries are not used for cross-app tracking, advertising, or unrelated profiling. We process journal entries only to provide the analysis and learning features you request.

4) AI Processing, Data Sharing, and Consent

Lingle uses third-party service providers to deliver certain features. We do not send your personal data to third-party AI services unless and until you provide permission in the app.

A. What Data Is Sent to AI Services

If you choose to use AI-powered features, the app may send the minimum necessary data to generate a response, including:

  • journal text you submit
  • translation responses and written exercise responses you submit
  • quiz responses relevant to AI feedback
  • language-learning context needed to answer your request (for example, source/target language and task type)
  • if you include personal data (such as an email address) in submitted text, that text may be transmitted as part of your request

B. Who the Data Is Sent To

For AI features such as journal analysis, translation validation, benchmarking, and AI-generated exercises, the above content is transmitted securely to OpenAI (provider of the OpenAI API).

  • Only the minimum necessary content required to generate a response is transmitted.
  • OpenAI may retain API data for a limited period for security, abuse detection, and reliability purposes in accordance with its policies and applicable law.

C. Permission Before Sending Data to AI Services

Before first use of AI-powered features, Lingle asks for your permission in-app before sending eligible content to AI services (including the OpenAI API). If you do not grant permission, your content is not sent to AI services and AI-powered features remain disabled.

For clarity, journal entries are transmitted for AI analysis only when you explicitly submit or request that analysis.

D. Third-Party Protection Standard

We require third-party processors that receive personal data on our behalf to provide privacy and security protections that are the same as or substantially equivalent to the protections described in this Privacy Policy and required by applicable law.

E. External Content Sources

When the app fetches news or article content from third-party websites, those external sites may independently collect technical information according to their own privacy policies.

5) Data Storage

  • On-device storage: Profile data and learning progress are primarily stored locally on your device.
  • Remote processing: Content submitted for AI-based features is transmitted to backend services for processing.

6) Data Sharing

We do not sell personal information.

We share data only with service providers necessary to operate the app (such as AI processing providers and infrastructure services), and only for the purposes described in this Privacy Policy.

7) Data Retention

  • Locally stored data remains on your device until you delete it or uninstall the app.
  • Content transmitted for AI processing may be temporarily retained by service providers for security and reliability purposes.
  • We retain backend logs and operational data only as long as reasonably necessary for security, legal compliance, and service integrity.

8) International Data Transfers

Because Lingle relies on cloud-based infrastructure and AI processing services, information may be processed in countries outside your own. We rely on service providers that implement appropriate safeguards consistent with applicable data protection laws.

9) Children

Lingle is not intended for children under 13 (or the minimum age required by local law). We do not knowingly collect personal information from children in violation of applicable law.

10) Your Choices

  • You may choose what profile information to provide.
  • You may disable notifications in iOS Settings.
  • You may decline AI data-sharing permission and still use non-AI app features.
  • You may avoid submitting content to AI-based features at any time.
  • You may uninstall the app to remove locally stored data.

11) Security

We use reasonable administrative and technical safeguards intended to protect processed information. However, no system is completely secure.

12) Changes to This Policy

We may update this Privacy Policy from time to time. The updated version will be posted with a revised “Last updated” date.

13) Contact

For privacy-related inquiries: