Whio: EPUB & PDF Reader

Name: Whio: EPUB & PDF Reader
Rating: 4 (1 reviews)
Author: Nil Coalescing Limited

Technical books & code

Free · In‑App Purchases

1 Rating
Age Rating

4+
Years
Category

Books
Developer

Nil Coalescing Limited
Language

EN
English
Size

36.7
MB

Whio is an EPUB and PDF reader for technical books on iPhone and iPad, with a focus on readability and accessibility. Technical books are full of code, and most readers aren't built for it. Whio keeps code examples readable, with clear syntax highlighting, preserved indentation and horizontal scrolling for long lines. You can zoom into a single example to look at it closely, or copy it to try it yourself. CUSTOMIZE TEXT AND CODE SEPARATELY Set the typography for prose and for code independently, so each one reads the way you prefer. THEMES FOR YOUR READING NEEDS Choose from high-contrast themes, softer contrast and tinted backgrounds, each available in light and dark versions. EXTRA SUPPORT AS YOU READ Enable optional reading aids if needed. Letter distinction gives letters more definition, so similar letters are easier to tell apart. A reading guide helps you keep your place on the page, and a focus window dims the text around the lines you're reading. YOUR NOTEBOOK Highlight passages, add notes and bookmarks, and find them again with search. You can export everything you've saved. Whio comes with its own collection of original technical books you can read in full for free, and every reading feature is included. Import your own DRM-free EPUBs and PDFs and read a short free preview of each one. Upgrade to Whio Unlimited to read every book you import in full, with a subscription or a one-time purchase. The app and all in-app purchases are licensed under the standard Apple terms: https://www.apple.com/legal/internet-services/itunes/dev/stdeula

Ratings & Reviews

4.0

out of 5

1 Ratings

Good App. Doesn’t Render Syntax Highlighting Consistently Though
3d ago
tlatkins
It’s a great app for reading technical books. The ability to scroll instead of turn pages is much better when dealing with code. My only issue was that not every book rendered code with syntax highlighting. Mohammed Azam’s “SwiftUI Architecture” and “SwiftData Architecture” didn’t show any syntax highlighting. It was still better to read in Whio than Books because of the scrolling and the fact that the code word wraps instead of being cut off on the right.
Good App. Doesn’t Render Syntax Highlighting Consistently Though
3d ago
tlatkins

It’s a great app for reading technical books. The ability to scroll instead of turn pages is much better when dealing with code. My only issue was that not every book rendered code with syntax highlighting. Mohammed Azam’s “SwiftUI Architecture” and “SwiftData Architecture” didn’t show any syntax highlighting. It was still better to read in Whio than Books because of the scrolling and the fact that the code word wraps instead of being cut off on the right.

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Supported Features
- VoiceOver
- Larger Text
- Dark Interface
- Sufficient Contrast

Information

Seller: Nil Coalescing Limited
Size: 36.7 MB
Category: Books
Compatibility: Requires iOS 26.0 or later.

iPhone
Requires iOS 26.0 or later.

iPad
Requires iPadOS 26.0 or later.
Languages: English
Age Rating: 4+

4+

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In-App Purchases: Yes

Lifetime Unlimited $49.99

Unlimited $24.99

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Copyright: © 2026 Nil Coalescing Limited