Privacy Policy

Manguage (“the app”) is built to put your privacy first. No sign-up with a name or email is required, and the manga images and cards you create stay on your device by default. The optional referral, team and save-time AI explanation features use an anonymous account only when you use them (§4). This policy explains what the app does — and does not — do with data.

1. What never leaves your device

• Manga photos and images. Imported images are not sent off your device. Text recognition (OCR) runs on-device.
• Flashcards, decks, study history, XP and streaks. All stored on your device. We do not keep them on our servers.
• Any optional on-device backup you create is saved to a location you choose (your device or your own cloud drive); we are not involved.

2. What is sent for translation

• By default the app uses online translation. The only thing sent is the text recognized from the image (the dialogue). The image itself is never sent.
• Route: the text passes through our relay server (Cloudflare Workers) and is translated by the US inference services Together AI (normally) or Groq (as a fallback during outages). The translation models are open models (such as DeepSeek) run on each provider’s own infrastructure — your text is never shared with the model developers.
• Storage and training: our relay server neither stores nor logs your text. Neither Together AI nor Groq uses your text to train models, and both are configured for Zero Data Retention.
• Questions to the in-app AI. If you ask the AI about a line, the text you type (and the recognized line it refers to) is sent by the same route. No image is sent, and your questions are not used to train models.
• Dialogue explanations when saving a sentence card: if you study Japanese, have agreed to online translation and use automatic translation, saving a sentence card sends that line’s text and on-device dictionary candidates to Together AI through the same route to pick the meaning that fits the context. Images are not sent.
• If you add the “Offline Pack”, translation runs on-device when you have no signal, and no text is sent (optional feature).
• All transmissions are encrypted (HTTPS).

3. Information collected automatically

Besides translation (§2), the app uses the following third-party services (all Google):

Ads are shown only in the free version. Before ads appear, the app runs consent management (UMP) as required by your region, and on iOS shows App Tracking Transparency. If you decline, ads are non-personalized.

4. Friend referrals, Teams and AI explanation limits (optional)

Referrals and Teams are optional features. Only when you use them, or the dialogue explanation (AI analysis) when saving a sentence card, does the app create an anonymous account (Firebase Anonymous Auth). No name and no email address is required, and none is collected. If you never use referrals or Teams, none of the Firestore records below are created.

For AI analysis, to prevent abuse and enforce a daily usage limit, our relay server verifies your anonymous ID and records only an irreversible hash of it and that day’s usage count. The record is replaced on your first use on the next day (UTC). Neither the anonymous ID nor its hash is sent to AI inference services such as Together AI.

What is stored in our Firebase (Firestore):

• Your anonymous Firebase UID
• The team name you type in
• The team ID and the invite code
• Timestamps and status for joining, goal achievement, cheers, rewards, leaving and reports
• The UTC offset at the time the team was created
• The guideline version, the reward tier, and anonymous aggregate counts

What other members can see is only anonymous aggregates: the team name, the current number of members, how many members have achieved the goal, the number of cheers, and similar totals.

Other members never see your UID, your name, your email address, or your individual study history — the app does not hold a name or email for you at all.

5. Team notifications

• On devices where you enable notifications, the app stores the FCM registration token, the OS, the display language and the time it was last updated in Firebase.
• The FCM token is used only to deliver notifications such as cheers, a member joining, a member leaving, and the team reaching its goal.
• It is never used for advertising, tracking or profiling.

6. What is never stored or shared with a team

The app does not send any of the following to a team or to other members:

• Manga images and screenshots, dialogue text, work/series titles
• Flashcards, translations, and your questions to the AI
• XP and streaks
• Your name, email address, contacts, device name, and precise location

Manga images and text recognition (OCR) continue to be processed on your device as described in §1. There is no chat feature and no free-text cheer message — cheers are fixed, content-free signals.

7. Children’s privacy

The app is intended for a general audience and does not knowingly collect personal information from children under 13 (or the age defined by your region).

8. Your choices and data deletion

• Deleting the app removes all study data from your device.
• You can change ad personalization at any time from your device’s ad settings or the app’s consent reset.
• Data deletion in the app. The data-deletion action inside the app deletes your anonymous referral and team records, your notification token, and your anonymous account. For step-by-step instructions and a full breakdown of deleted and retained data, see Delete your Manguage data.
• Exception: records needed to prevent abuse of the reporting feature may be retained, with the anonymous UID de-identified so it can no longer be linked back to you.
• If you have any question about deletion, contact us at the address below.

9. Sharing with third parties

We do not sell or share your information with third parties except as needed to provide the services above (the translation processing in §2, the Google services in §3, and the Firebase Firestore / Firebase Cloud Messaging storage and delivery in §4–§5). Each service handles data under its own privacy policy (Google, Together AI, Groq and Cloudflare respectively).

10. Changes

If we update this policy, we will revise the “Last updated” date on this page.

11. Contact

Sakiparu — k2@saki-paru.com