Four reading modes
Choose Flow, Line Lock, Focus Stream or a traditional ebook layout. Add word tracking when you want the current word highlighted.
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RIVI
A line of focus.
Line highlighting, adjustable pacing and a library for your own books.
In development · Android first
Line Lock in action
WHY RIVI?
Why RIVI?
Rivi means “line” in Finnish. It began with a simple idea: a line of focus to help you keep your place as you read.
Line highlighting, Line Lock and Bionic Reading offer different ways to follow the text. Choose the type and spacing that feel comfortable.
Choose from Georgia, Literata, a sans-serif font, Atkinson Hyperlegible, or OpenDyslexic.
READING
Reading features
Type and themes
Choose Bionic Reading, adjust type size and spacing, and switch between day, night and sepia themes.
Your library
Keep books organised with categories, favourites and series. Bookmarks and saved progress help you pick up where you left off.
LIBRARY
Keep your books together.
Import your own DRM-free books and keep your place between sessions.
Your books, preferences and progress stay on your device. With Premium, you can browse and import free public-domain books from the Project Gutenberg catalogue.
Compare Free and Premium for library limits and included features.
SUPPORTED FORMATS
Supported formats
| Format | Reading support |
|---|---|
| EPUB, TXT, HTML, Markdown (.md), FB2 | Full RIVI reading features |
| Basic document viewing only. RIVI’s highlighting and guided-reading features are unavailable. |
FREE & PREMIUM
Free and Premium
Free includes every reading mode and up to five books. Premium adds an unlimited library and the tools below.
| Feature | Free | Premium |
|---|---|---|
| Library size | Up to 5 books | No app-imposed limit |
| Line highlighting, Line Lock & adjustable pacing | Included | Included |
| Bionic Reading & supported file formats | Included | Included |
| Bookmarks, search & saved reading position | Included | Included |
| Built-in themes, typography & accessibility tools | Included | Included |
| Reading statisticsOn-device reading time, pace, activity and per-book insights | Not included | Included |
| Custom reading themesCreate your own palettes with contrast checks | Not included | Included |
| Series managementSet reading order and continue to the next volume | Not included | Included |
| Automatic category suggestionsReview suggestions before applying them | Not included | Included |
| Built-in Project Gutenberg catalogueDiscover and import public-domain books inside RIVI | Not included | Included |
Both options include the same features. Prices are shown in the app store before purchase.
What happens if Monthly expires?
Your existing books remain readable, even if your library contains more than five books. All Free reading features stay available. Premium features become unavailable, and new imports resume when your library has fewer than five books or you reactivate Premium.
RIVI is still in development. This comparison reflects the current app; final availability and store offers will be confirmed at release.
RIVI · PRIVACY
Privacy policy
Last updated 11 October 2026
This policy describes how RIVI, made by Kapy Labs, handles information. RIVI stores your reading library locally. Optional online features involve the services described below.
Books and reading data
Imported book files, extracted resources, library metadata, reading positions, bookmarks, categories, preferences, custom themes, reading statistics, recent free-book searches and dictionary results are stored on your device. A folder location may also be saved when you choose a folder for scanning.
RIVI does not upload your library or reading history to a Kapy Labs server, and does not require a RIVI account.
Optional online features
When you search the free-book catalog, RIVI sends the search query and requests for book metadata to Gutendex and may request additional metadata from Open Library. Book details, covers and book files may be requested from Project Gutenberg. These services receive normal connection information such as your IP address.
When you look up a word, RIVI sends that word and the selected dictionary language to Free Dictionary API and English Wiktionary. If they do not return a result, RIVI may use Datamuse as a fallback. Results are cached locally so the same definition can be opened again without a new request.
Project Gutenberg privacy policy
Purchases and Premium
In store builds configured for purchases, RIVI uses RevenueCat and the platform app store to check Premium access, process purchases and restore purchases. RevenueCat uses an app user identifier and purchase information for entitlement management and purchase reporting. Payment details are handled by the app store rather than entered into RIVI.
Analytics and advertising
RIVI has no advertising or separate reading-behaviour analytics SDK. Your reading statistics stay on your device. RevenueCat’s purchase reporting is separate from those local reading statistics.
Files, backups and device controls
RIVI does not currently ask for access to your camera, microphone, location, contacts or photo library. Files and folders become available to RIVI only when you choose them through the system picker.
Imported copies are kept in the app’s private storage. Exported backups are saved to the destination you choose; that destination may have its own privacy practices.
When optional shake controls are enabled, RIVI reads accelerometer data while the reader is open and the app is active. This data is processed on your device to control reading playback; it is not stored or sent to Kapy Labs.
Security
RIVI keeps imported books and its database in app-private storage and uses encrypted HTTPS connections for the online features described above. No storage or transmission method can be guaranteed completely secure.
Keeping and removing information
Local information remains until you remove it, erase RIVI’s data or uninstall the app. Removing a book from RIVI removes its imported copy and related library data; it does not delete your original source file.
Exported backups and device-system backups are managed separately. Uninstalling RIVI does not cancel an app-store subscription or delete purchase records held by the store or RevenueCat.
Contact and updates
Kapy Labs is responsible for RIVI’s app-specific data handling. If you contact us, we receive the information you choose to send.
This policy may be updated as RIVI develops. The date at the top identifies the current version.