Whitespace.
See who already built your idea — and the space they left open.

CLUSTER CLOUD-READER-READING · 43 ENTRIES · EARLIEST ENTRY 2012-05-31

Ebook readers and converters

This cluster comprises 26 products centered on ebook reading and format conversion, offering features like annotation, cloud sync, and multi-format support. Their dated entries appear sporadically from October 2010 to July 2026, usually one per month with occasional months having two, showing no clear trend in growth. Among traction leaders, Lorebound has the highest activity signal with 2 stars, while Thorium Reader and Syncer have 0 stars each.

Entry timeline

ENTRY TIMELINE

AUG 2009: 1MAY 2012: 1JUN 2012: 1DEC 2013: 1JUN 2014: 1SEP 2016: 1AUG 2019: 1DEC 2019: 1JAN 2021: 1MAY 2021: 1DEC 2021: 1OCT 2023: 1APR 2024: 1NOV 2024: 1JAN 2025: 1APR 2025: 1JUN 2025: 1JUL 2025: 1OCT 2025: 2APR 2026: 2JUL 2026: 5AUG 2026: 7SEP 2026: 8OCT 2026: 1
AUG 2009OCT 2026

Each bar is the month a member carries, which is a creation date where the source published one and a crawl date otherwise. Nothing in the index was found before 11 August 2026, and coverage broadened sharply on 14–15 August, so a bar from then on reports how much we found that month, not how much was built; an earlier bar reports how far back a member's own source dated it — not how long we have been watching.

Members by activity

Activity signals, not revenue.

Build origin · 4 hand-coded · 16 unlabelled

Operator · 1 hobby · 1 indie · 4 commercial · 8 open source · 6 unlabelled

Two labels per entry, never collapsed into one: how it was built, and who stands behind it. Counted over the 20 listed below. Unlabelled means nothing has decided yet — not that the answer is small.

  1. 21KOReader0★2 molivehand-codedopen sourceEbook reader optimized for e-ink screens that supports many formats, customizable typesetting, and reading progress synchronization across devices.
  2. 22Koodo Reader0★2 moliveopen sourceEbook reader that organizes and syncs a personal library across devices with highlights, notes, and reading customization.
  3. 23Zents - eBook Reader0★13 daysliveindieCloud-based ebook reader that imports many formats, syncs progress across devices, and supports offline reading.
  4. 24csBooks - ePub and PDF reader0★17 daysliveE-book reader that imports and organizes EPUB, PDF, MOBI, and comic files for offline reading with cloud backup and reading progress tracking.
  5. 25eBoox - fb2 ePub book reader0★4 molivecommercialEbook reader supporting many formats with offline reading, custom fonts, highlights, and cloud synchronization of progress.
  6. 26Omnia Reader0★2 moliveUniversal e-book reader that opens many formats offline with no ads or tracking, and offers on-device AI summaries and translation as paid features.
  7. 27HiReader - EPUB & PDF Reader0★4 moliveLocal ebook reader app that supports common document formats and provides reading statistics, bookmarks, notes, cloud sync, and customizable layout.
  8. 28coolreader0★4 moliveopen sourceEBook reader supporting XML and CSS formats.
  9. 29The Ebook Converter0★6 mostalelivecommercialApp that converts ebooks between many formats, with cloud and local conversion options.
  10. 30crqt-ng0★1 yrabandonedliveopen sourceCross-platform e-book reader supporting multiple formats with dual-page display, text search, customizable fonts, and a tabbed reading interface.
  11. 31EPUB Reader - Neat0★2 yrabandonedlivecommercialCross-platform EPUB reader with cloud storage, annotations, and customizable reading experience.
  12. 32EasyReadz0★5 yrabandonedlivehand-codedEbook reader supporting EPUB and PDF with customizable fonts, cloud sync, and cross-device progress.
  13. 33Scrolex0★unknownlivehobbyEbook reader that lays out PDF and ebook pages side by side for horizontal scrolling, with dark mode and text search.
  14. 34TotalReader Pro - ePub, DjVu, MOBI, FB2 Reader0★9 yrabandonedlivehand-codedcommercialReader application that supports a wide range of book, office, and comic formats, integrating with cloud services and network file sharing.
  15. 35Anx Reader0★6 mostaleliveopen sourceE-book reader that supports multiple formats, synchronizes reading progress across devices, and offers AI summaries and reading statistics.
  16. 36crengine-ng0★10 mostaleliveopen sourceCross-platform library for building text viewers and ebook readers.
  17. 37BerryPaper0★11 mostaleliveopen sourceDesktop client that browses, downloads, and tracks official Raspberry Pi magazines and books in PDF format for offline reading.
  18. 38Koodo Reader0★unknownliveopen sourceCross-platform ebook manager and reader supporting many formats, cloud sync, AI translation and summarization, annotations, and customizable reading themes.
  19. 39i2Reader0★11 yrabandonedlivehand-codedEbook reader app that supports multiple document formats, dictionaries, custom styles, and autoscroll, with tools to transfer books from a computer.
  20. 40Calibre0★unknownliveApplication that manages e-book libraries, converts between formats, fetches metadata, and syncs to reader devices.

Ranked by traction, highest first, and paged 20 at a time — this is a window on the cluster, never the whole of it. Ties are broken by a stable id so a product cannot appear on two pages or fall between them. Browse every cluster.