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Kafka provides dedicated readers for PDFs and EPUBs, allowing you to read books and documents with a tailored experience for each format.

Opening Books for Reading

1

Find a Book

Browse or search for books. Look for items marked as PDF or EPUB in their media type indicator.
2

Open Item Details

Tap on the book to view its details page.
3

Start Reading

Tap the primary action button (labeled “Read” or “Open”) to begin reading. The appropriate reader will open based on the file type.
Alternatively, you can:
  • Access the files list by tapping the download icon
  • Filter to show only PDF or EPUB files
  • Tap a specific file to open it in the reader
Download books before reading for a faster, more reliable reading experience, especially for large PDFs.

PDF Reader

The PDF reader is optimized for reading PDF documents and scanned books.

PDF Reader Features

  • Page Navigation: Swipe vertically to move between pages
  • Zoom Controls: Pinch to zoom in and out
  • Page Counter: View current page and total pages
  • Auto-Resume: Automatically returns to your last read page
  • Smooth Scrolling: Continuous page scrolling for comfortable reading

Reading PDFs

1

Open PDF

Tap a PDF file to open it in the PDF reader.
2

Navigate Pages

Swipe up and down to move through pages. The current page number appears as you scroll.
3

Zoom for Detail

Pinch to zoom in on text or images. Pan around the zoomed page by dragging.
4

Toggle Controls

Tap the center of the screen to show or hide the reader controls and page information.

PDF Reading Tips

  • Page Position Saving: Your current page is automatically saved every few seconds
  • Large PDFs: For better performance with large PDFs, download the file first
  • Scanned Pages: Use zoom to read scanned text clearly
  • Landscape Mode: Rotate your device for wider pages or two-page spreads
PDF page numbers are saved automatically. When you return to a PDF, it opens to your last position.

EPUB Reader

The EPUB reader provides a customizable reading experience for EPUB ebooks.

EPUB Reader Features

  • Reflowable Text: Text adjusts to your screen size and preferences
  • Font Customization: Change font family, size, and line height
  • Background Colors: Choose from multiple background color options
  • Chapter Navigation: Navigate through book chapters seamlessly
  • Reading Settings: Customize your reading experience

Reading EPUBs

1

Open EPUB

Tap an EPUB file to open it in the EPUB reader.
2

Read and Scroll

Scroll vertically to read through the book. Text flows naturally based on your screen size.
3

Access Settings

Tap anywhere on the screen to open the reading settings sheet.
4

Customize Reading Experience

Adjust font size, font family, or background color from the settings sheet.

Customizing EPUB Settings

The EPUB reader offers extensive customization options:

Font Size

  • Drag the font size slider to adjust text size
  • Choose from 7 different font sizes (12sp to 24sp)
  • Line height adjusts automatically with font size
  • Preview changes in real-time as you adjust
1

Open Settings

Tap the screen to show the settings sheet.
2

Adjust Font Size

Use the slider under “Font Size” to make text larger or smaller.
3

Preview Changes

Changes apply immediately - continue reading to test the new size.

Font Style

Choose from four font families:
  • Serif: Traditional, classic reading font (default)
  • Sans Serif: Modern, clean font for easy reading
  • Monospace: Fixed-width font, useful for technical content
  • Cursive: Decorative font for a unique reading experience
Tap any font name to switch to that font family.

Background Color

Select from multiple background colors optimized for reading: Light Mode Options:
  • White (default surface)
  • Light gray
  • Warm cream/sepia
  • Cool gray
  • Ivory white
  • Soft pink
Dark Mode Options:
  • Dark surface (default)
  • Medium gray
  • True black
  • Deep charcoal
  • Warm dark
  • OLED black
For reduced eye strain, try the warm cream background in light mode or the OLED black background in dark mode.

EPUB Reading Tips

  • Settings are modal - adjust them, then tap outside to continue reading
  • Text automatically reflows when you change settings
  • Font and background combinations can improve reading comfort
  • Larger fonts are great for reading in bright light or at distance
  • Serif fonts are generally easier to read for long-form content
EPUB settings apply to the current reading session. Your preferences are remembered for future sessions.

General Reading Features

Progress Saving

Both readers automatically save your progress:
  • PDFs: Current page number is saved
  • EPUBs: Reading position within chapters is tracked
  • Progress updates every few seconds while reading
  • Resume from the homepage “Continue Reading” section

Continuing Your Reading

1

Find Your Book

Books you’ve started appear in “Continue Reading” on the homepage.
2

Quick Resume

Tap the book card to immediately resume reading from your last position.
3

Or From Item Details

Navigate to the book’s details page and tap “Continue” to resume.
Progress is indicated by a visual progress bar on the “Continue Reading” cards.

Reading Modes

Online Reading (Streaming):
  • Reads directly from the Internet Archive
  • Requires internet connection
  • Instant access
  • No storage used
Offline Reading (Downloaded):
  • Download files to your device
  • No internet needed
  • Faster page loads
  • Reliable access
  • Uses device storage
For offline reading instructions, see the Offline Usage guide.

Reader Controls

Common Controls

  • Tap Center: Show/hide controls and settings
  • Swipe: Navigate through content
  • Pinch (PDF only): Zoom in/out
  • Back Button: Exit reader and save progress

System Integration

  • Use your device’s back button to exit the reader
  • Status bar can be hidden for immersive reading
  • System brightness controls affect reader display
  • Rotation lock can keep orientation fixed
Enable your device’s blue light filter or night mode for comfortable evening reading.

Troubleshooting Reading Issues

File Won’t Open

  • Check your internet connection for online reading
  • Try downloading the file first for offline reading
  • Ensure the file format is PDF or EPUB
  • Some very large files may take time to load

PDF Pages Not Loading

  • Download the PDF for better performance
  • Check available storage space
  • Try a different quality version from the files list
  • Close and reopen the reader

EPUB Formatting Issues

  • Try adjusting font size and family
  • Some EPUBs may have embedded formatting that overrides settings
  • Restart the reader if text doesn’t reflow properly

Progress Not Saving

  • Ensure you’re signed in (even anonymously)
  • Check that storage permissions are granted
  • Don’t force-close the app while reading
  • Allow the app to run in the background
For the most reliable reading experience, download books for offline use and ensure adequate device storage.

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