# Niraqua DjVu Help

> Getting started with Niraqua DjVu, a DjVu viewer and PDF converter for Mac, iPhone, and iPad.

Source: https://niraqua.com/djvu/help/

Reading, text recognition, and PDF conversion run on your device. Download cloud files before opening them. Cloud storage and sharing use the services you choose.

It is a universal purchase: buy it once and use it on all three.

**On iPhone or iPad?** Everything specific to those apps - opening files,
reading, searching, selecting and copying text, recognizing text, exporting,
printing and sharing - is on [On iPhone and iPad](https://niraqua.com/djvu/help/ios/). The rest
of this help describes the Mac app; the two share the same engine, so the
topic pages below still explain what each feature does.

Requires macOS 14 Sonoma or later, or iOS 26 / iPadOS 26 or later.

## What you can do

- **Read** `.djvu` files with continuous or two-page layouts, smooth zoom, and
  fit-to-window.
- **Search and select** text, and copy it to the clipboard.
- **Recognize text** on scanned pages with on-device OCR so they become
  searchable.
- **Duplicate, rename, or move** the original `.djvu`.
- **Share** the original `.djvu` through the macOS share sheet.
- **Export to PDF** - all pages, the current page, or a page range - with a
  quality preset and an optional searchable text layer.
- **Print** any open document through the standard macOS print dialog.
- **Quick Look** a `.djvu` file in Finder without opening the app.

## Why large files stay fast

Niraqua opens local files with memory-mapped I/O, so it does not need to copy
an entire book into memory before you can start reading. It decodes pages on
demand, reuses prepared page data, preloads nearby pages, and keeps that work
within a memory budget chosen for your device.

The reader and PDF exporter share a native Rust engine. Its busiest image
processing loops use SIMD vector operations, which compile to NEON instructions
on Apple silicon. The result is fast opening, smooth navigation through long,
image-heavy documents, and quick PDF conversion without uploading the file.

## Quick start on Mac

1. [Open a document](https://niraqua.com/djvu/help/opening/) by double-clicking a `.djvu` file in Finder.
2. [Read and navigate](https://niraqua.com/djvu/help/reading/) with the scroll wheel, the zoom shortcuts,
   or the thumbnail sidebar.
3. If the page has no usable text, run text recognition. [Search DjVu files and recognize scanned text](https://niraqua.com/djvu/search-djvu/)
4. [Export to PDF](https://niraqua.com/djvu/help/exporting/) when you want to share or archive the
   document.

## All topics

- [Opening a document](https://niraqua.com/djvu/help/opening/)
- [Reading and navigation](https://niraqua.com/djvu/help/reading/)
- [Contents and bookmarks](https://niraqua.com/djvu/help/contents-bookmarks/)
- [Search and text selection](https://niraqua.com/djvu/help/searching/)
- [Text recognition (OCR)](https://niraqua.com/djvu/help/text-recognition/)
- [Saving and exporting](https://niraqua.com/djvu/help/exporting/)
- [Printing](https://niraqua.com/djvu/help/printing/)
- [Quick Look](https://niraqua.com/djvu/help/quick-look/)
- [On iPhone and iPad](https://niraqua.com/djvu/help/ios/)
- [Keyboard shortcuts](https://niraqua.com/djvu/help/shortcuts/)
- [Troubleshooting](https://niraqua.com/djvu/help/troubleshooting/)

## Need more help?

Email [support@niraqua.com](mailto:support@niraqua.com) and we will get back to you.