Privacy Policy
Last updated: November 2026
NidNoi ("we", "our", or "the app") is a language learning app. This policy explains what information the app uses and how it is handled.
Summary
You can use NidNoi without an account — progress is stored on your device. If you choose to sign in (Apple, Google, or email), we sync your learning progress through our secure API so you can restore it on a new device. We collect first-party product analytics tied to an install (and to your account when signed in). We do not sell your information or use it for advertising tracking.
Information stored on your device
The app stores the following locally:
- Words you mark as learned and lessons or grammar units completed
- Quiz scores, streaks, and milestone progress
- Settings such as reading mode (hide romanization)
- Which alphabet characters you have viewed
This data is saved using your device's local storage (SharedPreferences on iOS/Android).
Optional sign-in and cloud sync
If you sign in, authentication is handled by Supabase (email, Apple, or Google). For email sign-in we collect your email address. Apple or Google may also share an account identifier and, depending on your settings, an email address. When you sync, we store a JSON snapshot of your learning progress (milestones, words learned, unit completion). Sync traffic goes through nidnoi-site API routes hosted on Vercel, using a service role key that never ships in the app.
You can use the app fully offline when sync is not configured or when you are signed out. Signing in is always optional.
Product analytics
When sync is configured, the app may send first-party journey analytics to help us improve the course. This can include a persistent install identifier; product interaction events (screens, course steps, feature usage, and sign-in funnel); device and locale context (language, timezone, OS version, screen metrics, and public IP); and, when you are signed in, a link to your account. If you attempt email sign-in, the address you entered may appear in funnel events.
This analytics data is linked to your identity (install and, when signed in, account). Events are stored in our Supabase nidnoi schema. They are not used for advertising, and we do not share them with data brokers or advertising networks for tracking.
Text-to-speech
When you tap listen on a word or example, the app uses your device's built-in text-to-speech engine. Audio is processed on your device; we do not receive recordings or transcripts.
Local streak reminders
If you opt in, NidNoi schedules a daily reminder on your device (around 7:00 pm local time) so you can keep a study streak. These are local notifications only. We do not send server push notifications, and we do not use reminder settings for advertising. You can turn reminders off in Settings.
App Store and Play reviews
After some learning milestones, the app may ask Apple or Google to show their standard in-app review dialog. Those platforms decide whether a prompt appears. We do not receive the text of reviews you write through that dialog.
What we do not do
- No advertising identifiers or third-party ad networks in the app
- No sale of personal data
- No requirement to create an account to learn
- No use of email or product analytics for App Store "tracking" (ads / data brokers)
App Store purchases
If you make in-app purchases in the future, payment is handled by Apple or Google. We receive only the information those platforms provide to developers (such as purchase status), not your full payment details.
Children
NidNoi is suitable for general audiences. We do not knowingly collect personal information from children through our own services beyond what is needed for optional account sign-in chosen by a parent or guardian.
Changes
We may update this policy from time to time. The "Last updated" date at the top will change when we do. Continued use of the app after changes means you accept the updated policy.
Contact
Questions about privacy? Email hello@nidnoi.dev or visit our support page.