Kairo vs Ledor

Kairo is a free Android app for reading DRM-free ebooks and documents in standard, adaptive RSVP, and Bionic Reading modes. The reader offers scrollable chapters, inline images, a table of contents, bookmarks, progress tracking, and a movable focus word. Adaptive RSVP aligns words with ORP and changes timing based on punctuation, word length, syllables, clauses, and readability. Bionic Reading emphasizes word beginnings while showing more sentence context. Reading profiles control pacing, typography, brightness, and focus, with six themes available. Focus mode provides a full-screen view and can optionally enable Android Do Not Disturb. Kairo 1.1 supports EPUB, MOBI, PRC, AZW, FB2, FB2.ZIP, DOCX, text-based PDF, TXT, Markdown, HTML, and HTM. Files must be DRM-free; scanned PDFs and OCR are unsupported. Imported content and reading data remain in private device storage.

Ledor is a free, open-source reader for RSVP, EPUB files, and web articles, available on Android, iOS, Linux, and the web. It offers RSVP, text-to-speech narration, and a traditional e-reader mode. Readers can import EPUBs or save articles by URL; Android users can also share a page with the app. Text-to-speech uses system voices, provides lock-screen controls, and supports speeds from 0.5× to 3×. Appearance settings cover colors, fonts, sizes, and positions, with light and dark themes and a live preview.

Ledor works offline, storing books and progress on the device. Optional Google Drive sync can carry the library, progress, bookmarks, ratings, sessions, and display settings across devices. The privacy policy says the app collects no data and has no analytics, ads, tracking, accounts, or servers of its own. Weekly and monthly reading charts and a shareable monthly recap are calculated on the device. The MIT-licensed free plan includes all features, with no ads or account required.