KOReader

KOReader is a document reader written for e-ink hardware and later ported outward. It runs on Kobo, Kindle, PocketBook and reMarkable devices, on Android, and on desktop Linux, and the interface is the same everywhere: built for slow screen refresh and a small number of buttons, which on a desktop feels unusual before it feels efficient.

Two rendering engines sit underneath. Reflowable formats — EPUB, FB2, MOBI, plain text and others — go through a text engine with control over font, weight, line spacing, margins, hyphenation and embedded style overrides. Fixed-layout documents — PDF, DjVu and comic book archives — go through a page engine with cropping, column reflow and contrast adjustment for scanned pages.

Around the reader sit dictionary lookup through StarDict files, Wikipedia lookup, translation, reading statistics, exportable highlights and notes, OPDS catalogue browsing, and reading-progress synchronisation across devices through a server that can be self-hosted.