Features
- Library
- Switch between grid view (large and small) and list view. Sort and filter to find what you want to read.
- Folders, Categories & Tags
- Use your iCloud folder structure as-is. On top of that, organize freely with shelff's own categories and tags.
- Metadata Editing
- Edit title, author, publisher, language, description, and more. Automatic import of metadata embedded in PDF files is also supported.
- Collections
- Group multi-volume works and magazine issues into a single collection with custom titles and ordering. A dedicated collection display mode supports grouping, sorting, and filtering.
Reading
- Display Settings
- Choose single page, two-up, or two-up with a cover page, and set the reading direction (left-to-right or right-to-left) per book. These settings are stored in iCloud alongside the metadata and sync across your devices.
- Crop
- Trim the margins of scanned PDFs so the page fills the screen. Odd and even pages can be cropped separately, and a “Mirrored” mode handles scans of bound books. The PDF file itself is never modified.
- Highlights & Comments
- Select text to add a colored highlight, optionally with a comment. Highlights are written into the PDF as standard annotations, so other PDF apps show them as-is. Saves are incremental, so OCR text layers are never lost.
- Table of Contents, Bookmarks & Search
- Jump to any page from the PDF's table of contents, your own bookmarks, or the list of highlights. Full-text search is supported. After jumping from the table of contents or a search result, you can go back to where you were.
- Reading Progress
- Your last read page is remembered automatically so you can pick up where you left off. A book becomes “Reading” when you start and “Finished” when you reach the end, and the status can be changed from the library at any time.
- Keyboard Navigation
- With an external keyboard connected, you can turn pages without touching the screen.
Your Data
- Everything Lives in iCloud
- Not just your PDF files — metadata and reading progress are also stored as JSON files in iCloud. If you're signed in with the same Apple ID, your reading progress and metadata sync automatically across devices.
- Open Metadata Format
- Metadata is stored as JSON files in iCloud in an openly specified, portable format. Other tools can read and write it alongside shelff.
- Organize your library with an AI Agent and the MCP Server
- On any Mac signed in with the same Apple ID, you can search and organize your PDF library using an AI agent and shelff-mcp.
Shortcuts, Siri & Spotlight
- Shortcuts
- The Shortcuts app offers “Open Book”, “Continue Reading”, and “Set Reading Status” actions. “Continue Reading” simply opens the book you read most recently, which makes it a good fit for the Lock Screen or the Action button.
- Spotlight
- Books in your library appear in Spotlight search, and tapping a result opens it directly in shelff (iOS 18 or later).
- Siri
- On iPadOS 27, tell Siri “Open <title> in shelff” or “Search <term> in shelff” and the library is shown filtered by what you said. As of September 15, 2026, this has been verified with Siri in English; support in other languages depends on iPadOS rolling out the new Siri to them.