ReadSync

Pick up exactly where you left off.

Open a PDF on your Mac, read to page 120, then pick up your iPhone. ReadSync opens the same document on the same page — with your highlights, notes and bookmarks already there.

No account. No subscription. No server.

Your iCloud
Mac Page 120
iPhone 120

Every reader has the same small daily annoyance: you close a document, open it again tomorrow, and you're back at page 1.

ReadSync remembers. Not just on this device — on all of them.

What You Get

📍

Your page, everywhere

Your reading position syncs through your own iCloud. No account to create, nothing to set up.

🖍

Highlights and notes

Five highlight colours and a note on any passage — all synced, all in one list you can tap to jump.

🌙

A reader that gets out of the way

Controls hide while you read. Night mode darkens the page without draining the colour from your highlights.

🔎

Find your place fast

Full-text search, the PDF's own table of contents, and bookmarks for the pages you return to.

🔒

Your files stay yours

Nothing is written into the PDF. Nothing is uploaded to anyone's server. Works fully offline.

📊

Reading stats

Total reading time, the last seven days, and progress on everything you've started.

Pro

How It Works

1

Add a document

From Files or iCloud Drive. Leave it where it is, or copy it into ReadSync to sync it across devices.

2

Read

Highlight, note, bookmark. Everything saves as you go.

3

Switch device

Open ReadSync on your other Mac or iPhone. Same document, same page.

Your files never leave your iCloud

Built entirely on Apple's own frameworks. Your documents and notes live in your private iCloud database — not on a server I own, because there isn't one. No account, no tracking of what you read, no ads.

Your original PDF is never modified — highlights are stored separately and drawn back on top. No internet? Everything works offline; syncing is a layer on top, never a requirement.

Read the full privacy policy

Pricing

Syncing is free for everyone. It costs me nothing, so it costs you nothing.

Free

Everything the app does, with two limits.

  • Sync across all your devices
  • Up to 5 documents
  • 10 highlights or notes per document
  • Everything else, in full

ReadSync Pro

One-time purchase. No subscription.

  • Unlimited documents
  • Unlimited highlights and notes
  • Reading statistics
  • One payment, on all your devices

Limits only apply to adding new things. Everything already in your library stays fully readable.

Requirements

iPhone & iPad — iOS 18 or later Mac — macOS 15 or later iCloud account for syncing PDF files
Download on the App Store