PDF Yaho

A free, open-source PDF reader and editor for macOS, built on Apple PDFKit. No account, no subscription, no telemetry.

Download for Mac (macOS 14+, Apple silicon and Intel) · pdfyaho.chanhee.kr

The app is not notarized yet. On first launch, open System Settings › Privacy & Security and choose Open Anyway, or run xattr -dr com.apple.quarantine "/Applications/PDF Yaho.app".

PDF Yaho covers the everyday features of commercial PDF editors such as PDF Expert: reading, annotating, signing, redacting, filling forms and rearranging pages. docs/feature-parity.md lists what is done and what is planned.

Using it

The toolbar holds the toolsets. Each one shows only the tools for one task, in a floating bar at the top of the page:

Toolset	Tools
Read	No tools. Select text for a Highlight / Underline / Strike / Copy menu.
Edit	The page's own text and images: retype, restyle, move, resize, replace, add, delete
Annotate	Highlight, underline, squiggly, strikeout, text, notes, callouts, stamps, images, links
Draw	Pen, marker, rectangles, ovals, lines, arrows, polygons, clouds
Fill & Sign	Text, checkmarks, crosses, dates, signatures and initials, stamps, form fields
Measure	Distance, perimeter and area at a scale you set
Redact	Black-box or white-out marks, Find and Redact, Apply
Scan	OCR, Enhance, clear margins, crop, page size, split book spreads
Pages	Large thumbnails. Select, drag to reorder, rotate, insert, copy/paste, extract, delete.

Hide toolsets you never use with the … button. Style sets colour, size, opacity, fill, line style and text formatting, for the active tool or the selected annotation. Click an annotation to move it, resize it, change it or delete it. Hold ⇧ to keep lines straight and shapes square. The Display button sets the page layout and theme, and opens a second document in split view.

Key	Tool	Key	Tool
V	Select	T	Text
H	Highlight	N	Note
U	Underline	R / O / L / A	Rectangle / Oval / Line / Arrow
K	Strikeout	G	Signature
P / M	Pen / Marker	X	Redact
E	Eraser	C / S	Crop / Snapshot
⌘1 … ⌘9	Toolsets	⌘D	Bookmark page
⌫	Delete selection	Arrow keys	Nudge selection (⇧ for 10 pt)

Features

• Home: recent and favourite documents, and a Tools page that opens a file straight into a task such as compressing or signing it.
• Read: continuous, single, two-page and book layouts. Day, night and sepia themes. Thumbnails, bookmarks, an editable outline, and an annotation list with filters. Search with match-case, whole-word and history. Back/forward history.
• Edit PDF: click a paragraph to retype it in place, in its own font and width, in any language. Move text and images, resize or replace images, add new text and images, and change font, size and colour. Every edit is one undo step.
• Compare: two PDFs side by side or stacked, with scroll and zoom kept in sync.
• Annotate: highlight, underline, strikeout, pen, marker, text, notes, rectangles, ovals, lines, arrows, polygons, stamps, images and links. Set colour, opacity, thickness, fill and dashed lines. Copy, paste, duplicate and reorder annotations, with full undo.
• Fill & sign: fill forms and create form fields. Keep several signatures and initials, drawn, typed or imported from an image. Add checkmarks, crosses and dates.
• Measure: distance, perimeter and area, at a drawing scale you set.
• Redact: mark areas or every match of a search, as black boxes or white-out. Applying them flattens the marked pages, so the text underneath is actually removed.
• Pages: reorder, rotate, insert (blank, file, images, clipboard), duplicate, delete, crop, trim margins, resize, extract, split and merge. Add page numbers, headers, footers and Bates numbers. Edit page labels (i, ii … then 1, 2 …).
• Save and share: Save As Flattened. Share or mail a copy, as is or flattened. Reduce file size with four quality levels. Protect the document with a password. Recognise text in scans (OCR, on device).
• Convert: export to Word, Excel (tables become sheets), PowerPoint (a slide per page with editable text), RTF, HTML, text, Markdown, PNG/JPEG/TIFF or XFDF. Turn Word, RTF, HTML, Markdown, text and image files into PDF.

Requirements

macOS 14 or later. Building needs Xcode 16 or the Swift 6 toolchain.

Build

scripts/fetch-pdfium.sh         # once: pinned PDFium for Edit mode (build-app.sh runs it too)
scripts/build-app.sh            # universal release build → build/PDF Yaho.app
ARCHS=arm64 scripts/build-app.sh debug
open "build/PDF Yaho.app"
swift test                      # unit tests for PDFYahoCore

Editing page content uses PDFium (BSD-3/Apache-2.0), from the prebuilt pdfium-binaries release pinned in scripts/fetch-pdfium.sh. It is bundled in Contents/Frameworks with its licences in Contents/Resources/Licenses/PDFium. Without Vendor/pdfium the package still builds, with Edit mode turned off.

The app is ad-hoc signed. The first time you open a copy built on another Mac, right-click it and choose Open.

Layout

Path	Contents
Sources/PDFYahoCore	UI-free document operations: page edits, annotation factories, export, signatures. Unit tested.
Sources/PDFYaho	SwiftUI app: document window, PDF view and tools, sidebar, menus.
Tests/PDFYahoCoreTests	XCTest suite for the core.
Sources/CPDFium	Module map for the vendored PDFium headers.
scripts/build-app.sh	Builds the .app bundle.
site/	The landing page at pdfyaho.chanhee.kr (static, deployed with Wrangler).
scripts/fetch-pdfium.sh	Downloads and checks the pinned PDFium into Vendor/pdfium.
scripts/make-icon.sh	Builds Resources/AppIcon.icns from Resources/AppIcon-source.png.

Clean-room note

PDF Yaho is not affiliated with Readdle or PDF Expert. The reference app was examined only to list its features (see docs/feature-parity.md). No code, assets or text from it are included.

License

MIT. See LICENSE.