Privacy Policy for Noi

Last updated: October 15, 2026

Noi is a language-learning application for Android (package name com.noi.learning). This Privacy Policy explains what information Noi collects, how that information is used, and the choices available to you.

Information We Collect

When you use Noi, we may collect and store information necessary to provide the application's features, including:

• Account information. Noi uses Firebase Authentication to allow users to create and access an account. Depending on the sign-in method you use, this may include your email address and a Firebase user identifier. If you sign in with Google, Google Sign-In is used to authenticate you.
• Learning and app-use data. Noi stores information about your activity within the application so your learning experience can be saved and synchronized. This may include lesson progress, quiz answers and outcomes, question types attempted, vocabulary targets, passive-listening exposure, difficulty and settings preferences, and labels you assign to words.
• Usage and session data. Noi may record information about how you navigate the app, such as screens visited, settings changes, and timing related to loading lessons. This helps us understand app usage and improve reliability.
• Crash and diagnostic information. Noi uses Firebase Crashlytics to identify crashes and technical problems. Crashlytics may collect diagnostic information about the application, your device, app version, and circumstances surrounding a crash.
• Analytics information. Noi includes the Firebase Analytics SDK, which may automatically collect usage and device-related information (such as app interactions and technical identifiers) to help us understand how the app is used and to improve its performance. Noi does not display advertisements.
• Purchase and subscription information. If you subscribe to Noi Premium, payment is handled by Google Play. Noi never receives your card or bank details. We receive information about your purchase, such as the product purchased, purchase and renewal dates, subscription status, the purchase token issued by Google Play, and the country and currency of the purchase. This information is linked to your Firebase user identifier so your subscription stays with your account.
• Downloaded content. Lesson audio, icons, and related media may be downloaded from Firebase Storage while you are signed in and cached locally on your device so the app can function offline or with reduced network use.
• Local device storage. Noi stores a local copy of some learning data, settings, and cached media on your device using on-device databases and storage mechanisms.

Information We Do Not Collect

Noi does not:

• Display advertisements or use an advertising SDK
• Record audio from your microphone
• Access your camera, contacts, or precise location
• Sell your personal information

How We Use Information

We use the information described above to:

• Provide, operate, and maintain Noi
• Authenticate users and synchronize learning progress across sessions
• Deliver lesson content and personalized learning features
• Process subscriptions, confirm your access to premium lessons, and restore purchases
• Identify, troubleshoot, and fix crashes and technical problems
• Understand app usage and improve reliability and the learning experience

Third-Party Services

Noi uses Google Firebase and related Google services, including Firebase Authentication, Cloud Firestore, Cloud Storage, Firebase Analytics, Firebase Crashlytics, and Google Sign-In. Information processed through these services may be handled by Google in accordance with Google's applicable privacy policies and terms.

Google's SDKs may collect device and usage identifiers as part of standard analytics and crash-reporting behavior. This does not mean Noi shows ads; it reflects how Google's infrastructure processes diagnostic and usage data on our behalf.

For more information about how Google handles data, see Google's Privacy Policy.

Subscriptions are sold through Google Play Billing and managed with RevenueCat, a subscription service provider. RevenueCat receives your Firebase user identifier, the purchase information described above, and basic device and app information (such as app version, operating system version, and language) so it can validate purchases, track renewals and cancellations, and tell the app whether your subscription is active. See RevenueCat's Privacy Policy.

Data Sharing

We do not sell users' personal information. Information may be processed by service providers, such as Google Firebase and RevenueCat, when necessary to operate and maintain the application. We do not share your personal information with third parties for their own marketing purposes.

Data Security

We take reasonable measures to protect information stored and processed by the application. Data transmitted between the app and Firebase services is encrypted in transit. However, no electronic storage or transmission system can be guaranteed to be completely secure.

Data Retention and Deletion

Information may be retained for as long as necessary to provide the application and maintain your account. If you would like to request deletion of your account and associated personal data, contact us at the email address below. We will process deletion requests within a reasonable time. Deleting your account may remove your cloud-stored learning progress and associated data.

Deleting your account does not cancel a Google Play subscription. Cancel it first in the Google Play Store app (Profile → Payments & subscriptions → Subscriptions). Records of past purchases may be kept by Google and RevenueCat where needed for accounting, tax, fraud prevention, or legal reasons.

Children's Privacy

Noi is not directed specifically at children under 13, and we do not knowingly collect personal information from children under 13 without appropriate authorization. If you believe a child has provided us with personal information, please contact us and we will take steps to delete it.

Changes to This Privacy Policy

We may update this Privacy Policy as the application changes. Updates will be posted on this page with a revised “Last updated” date. Continued use of Noi after changes are posted constitutes acceptance of the updated policy.

Contact

If you have questions about this Privacy Policy or would like to request deletion of your account or associated data, contact:

noisoftwaresupport@gmail.com