Lumen Reader (“the app”, “we”) is an offline-first Android ebook reader with on-device text-to-speech narration. This policy explains what data the app does and does not handle.
The short version: Lumen Reader does not collect, store, transmit, or sell any personal data. There are no accounts, no analytics, no advertising, no tracking, and no crash reporting. Your books and all reading data stay on your device.
What stays on your device (never sent anywhere)
Your books — files you import are copied into the app’s private storage.
Reading data — reading positions, bookmarks, highlights, library, and settings, in a local database on the device.
Narration audio — speech is synthesized on the device and cached locally; no text or audio is sent to any server for narration.
When the app uses the network
The app works fully offline for reading and narration. It only makes network requests in these cases, and none of them send your personal data or reading activity to us:
Voice model download. On first use, the ~134 MB neural voice model is delivered by Google Play Asset Delivery (a standard Google Play mechanism). This is a download to your device.
OPDS catalog browsing (optional). Only when you choose to browse an online book catalog, the app requests the catalog feed and any book you download — directly from the catalog server you selected (e.g. Project Gutenberg). We do not operate or log these requests.
Purchases. In-app purchases are processed by Google Play Billing. Google handles your payment information per Google’s Privacy Policy; the app only receives whether you own the purchase. We never see your payment details.
Permissions
Internet — for the three network uses above.
Notifications (Android 13+) — to show playback controls while narrating; optional, you can deny it.
Foreground service / media playback — to keep narration playing with lock-screen controls.
The app does not request location, contacts, camera, microphone, or external-storage permissions.
Data sharing & third parties
We do not share data with third parties. The only third parties involved are Google Play (distribution, asset delivery, billing) and any OPDS catalog you explicitly choose to browse — each governed by their own privacy policies.
Children
Lumen Reader is not directed at children under 13 and does not knowingly collect data from anyone.
Changes
We may update this policy; the “Last updated” date will change accordingly.