NukoChineseShadowing ("the app") is an Android app for Taiwanese Mandarin shadowing
practice, developed by Nuko ("we", "our"). This page explains what data the app does —
and does not — handle.
Short version
The app's core features — automatic Zhuyin/Pinyin annotation, text-to-speech playback,
recording and comparing your own pronunciation, and managing your text list — all run
entirely on your device. We do not operate any server, and we never receive or store your
data. Data only leaves your device in the following cases:
AI pronunciation scoring (optional): if you enter your own Gemini API key in Settings, your recorded audio (together with the target sentence text) is sent directly from your device to Google's Gemini API, using your own key, and a pronunciation/tone assessment is sent back.
Camera text scanning (experimental): normal recognition uses Google's ML Kit on-device text recognition, runs entirely on your device, and the image is never uploaded. Only if you tap "Re-read with AI" and have set your own Gemini API key is that photo sent directly to Google's Gemini API, and the recognized text sent back.
Ads (Free version only): the Free version shows a banner ad at the top of the screen using Google's ad service, Google AdMob. To serve and measure ads, Google may collect and use your advertising ID, IP address, device information, and information about how ads are shown and interacted with. The Pro (paid) version shows no ads and makes none of these connections.
Pro purchase: upgrading to Pro is handled through Google Play Billing. Your payment details (such as card numbers) are never passed to us and are processed by Google Play. The app only receives whether you have purchased Pro.
About ads (Free version)
Ads in the Free version are served by Google AdMob, which may use your advertising ID and similar
data to show interest-based (personalized) ads. In the European Economic Area, the UK, and other
applicable regions, a consent form from Google's User Messaging Platform (UMP) is shown when you
first launch the Free version, and ads are served according to your choice. You can change your
choice at any time from "Ad privacy settings" in Settings. You can also delete or reset your
advertising ID at any time in Android's settings.
Your registered texts, bookmarks, recorded audio, settings (including any Gemini API key you
enter), and your Pro purchase status are stored only in the app's local storage on your device.
None of this leaves your device unless you explicitly use the "back up" feature to export a
backup file (other than the app checking your purchase status with Google Play, and the
optional AI features above). The backup file is written only to a location you choose, through
Android's standard file picker (the Storage Access Framework).
Permissions
Microphone (RECORD_AUDIO): used only when you tap the record button during shadowing practice, so you can compare your recording with the model audio, and — only if AI scoring is enabled — send it to the Gemini API as described above.
Internet (INTERNET): used only for ads in the Free version, checking your Pro purchase, and the optional AI features (AI pronunciation scoring and AI re-reading of camera scans). Every other feature works fully offline.
Advertising ID (AD_ID): used by Google AdMob to serve ads in the Free version. You can delete or reset your advertising ID at any time in Android's settings.
Camera: the app itself does not request camera permission. The camera text-scanning feature launches your device's own camera app to take the photo, and only receives the resulting image back.
Data collection and analytics
We do not collect:
Personal information (name, email, location, etc.)
Usage analytics or crash reports sent to any server of ours (we operate no server)
Your recordings, photos, entered texts, or API key
Data that Google AdMob collects to serve ads in the Free version (such as your advertising ID)
is handled by Google under its own privacy policy and is not received by us. Likewise, the
communication with the Gemini API (the optional AI features) happens directly between you and
Google and is not received by us.
Third-party services
The app integrates with the following third-party services, all provided by Google and each
governed by its own privacy policy:
Google Gemini API (only when you use the optional AI features, using your own API key, communicating directly from your device)
Google ML Kit (text recognition, fully on-device with no network transmission)
Google AdMob and Google User Messaging Platform (ads in the Free version, and consent collection in applicable regions)
Google Play Billing (processing the Pro purchase)
No other third-party SDK, analytics platform, or ad network is included.
Children's privacy
The app is not directed at children under 13 (or the relevant age in your country), and we do
not knowingly collect personal information from them. Ads in the Free version are served under
Google AdMob's own settings.
Changes to this policy
If this policy ever changes, this page will be updated and the "Last updated" date above
will change accordingly. Any such change would also be reflected in the app's in-app
description before release.
Contact
Questions about this policy or the app can be sent to: