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Reading Books

Features of the PDF and EPUB readers

Alex includes built-in readers for both PDF and EPUB formats. Click any book in your library to open it in a focused, full-screen reading view.

PDF reader

The PDF reader renders documents with page-by-page navigation. A toolbar at the top gives you access to all controls.

Navigation

  • Page buttons — Previous and next buttons step through pages one at a time.
  • Direct input — Type a page number into the input field to jump directly to any page.
  • Keyboard shortcuts — Left/Right arrows move between pages. Home jumps to the first page, End to the last.

The current page and total page count are always visible in the toolbar.

Zoom

  • Zoom in (+) and zoom out (−) adjust the view in 25% increments.
  • "Fit Width" scales the page to fill the browser width.
  • "Fit Page" scales to show the full page within the viewport.
  • The zoom range is 50% to 200%.
  • Keyboard shortcuts: + to zoom in, - to zoom out.

Text search

Press Ctrl+F (or Cmd+F on macOS) to open the search bar. Enter a term to highlight all matches on the current page. Use the next/previous buttons to step through results. Press Escape to close search and clear highlights.

EPUB reader

The EPUB reader handles reflowable text with customizable typography. Books are rendered in an 80ch-wide reading column for comfortable line lengths.

Chapter navigation

A table of contents button in the toolbar opens a sidebar listing all chapters. Click any chapter to jump to it. Previous/next chapter buttons in the toolbar let you step through the book's structure.

Page turning

  • Click or tap the left/right edges of the reading area to turn pages.
  • Swipe left or right on touch devices.
  • Use the Left/Right arrow keys on a keyboard.

Reading customization

Click the settings button in the toolbar to adjust:

  • Font size — Small (14px), Medium (16px), Large (18px), or Extra Large (20px).
  • Theme — Light (white background, dark text), Dark (dark background, light text), or Sepia (cream background, brown text).

Settings are saved in your browser and apply to all EPUBs.

Progress tracking

Both readers save your position automatically as you read. When you reopen a book, you pick up exactly where you left off.

Progress is tracked per user — each person's reading position is independent. A progress bar on each book card in the library shows how far you've read. Books are automatically marked as "reading" when you start and "completed" when you reach the end.