Comparison

ReadSync vs Red PDF Reader

Price, ratings, monetisation and update history for both apps, side by side β€” with what reviewers say about each.

Head to head
About

ReadSync

Features
Read full description

ReadSync remembers where you stopped reading β€” on every device. Open a PDF on your Mac, read to page 120, then pick up your iPhone. ReadSync opens the same document on the same page. Your highlights, notes and bookmarks are already there. WHY READSYNC β€’ Your reading position syncs automatically through iCloud β€” in the free version too β€’ No account to create, no subscription, no company server holding your files β€’ Works completely offline β€” syncing is a layer on top, never a requirement PICK UP WHERE YOU LEFT OFF β€’ A Continue Reading row at the top of your library, most recent first β€’ A Home Screen widget that opens the document on the page you left β€’ Nothing to press: the page is saved as you read and travels with you READING β€’ A quiet reader that hides its controls while you read β€’ Night mode that darkens the page without draining the colour from your highlights β€’ Single or two-page layout, vertical or horizontal scrolling β€’ Adjustable default zoom HIGHLIGHTS AND NOTES β€’ Five highlight colours β€’ Attach a note to any passage β€’ Every highlight and note in one list β€” tap to jump straight to the page β€’ Export everything from a document as a single file, to Notes, Mail or Files β€’ Nothing is written into the PDF itself; your original file stays untouched FINDING YOUR PLACE β€’ Full-text search inside the document β€’ The PDF's own table of contents β€’ Bookmarks for the pages you want to come back to YOUR LIBRARY β€’ Add files from Files or iCloud Drive β€’ Leave a file where it is, or copy it into ReadSync so it syncs across your devices β€’ Cover, progress and page count at a glance READING STATS β€’ Total reading time, and how much of it was this week β€’ A chart of the last seven days β€’ Progress for every document you have started FREE AND PRO The free version is a whole reader, not a demo: iCloud sync, night mode, search, table of contents, bookmarks and all five highlight colours, with room for 5 documents and 10 highlights or notes in each one. ReadSync Pro lifts both limits and opens reading stats, note export and the widget. It is a one-time purchase β€” there is no subscription. A limit only ever stops you adding something new. Everything already in your library stays open, in full, whether you buy or not. PRIVACY ReadSync is built entirely with Apple's own frameworks and stores everything in your private iCloud database. Your documents are never uploaded to anyone else's server. Anonymous usage statistics are sent only if you agree when asked, and never include your files, page contents, notes or highlights.

About

Red PDF Reader

Features
Read full description

Red PDF Reader A clean, distraction-free PDF reader designed for people who actually read. Open any PDF from your Files app and pick up exactly where you left off β€” Red PDF Reader remembers your last page automatically and syncs it across all your devices via iCloud. Switch from your iPhone to your iPad and continue reading without missing a beat. Features: Continuous reading β€” smooth, vertical scroll layout optimized for long documents Auto-resume β€” your last page is saved automatically and synced across devices Recent files β€” quickly jump back to any of your last 50 documents Page thumbnails β€” visual panel for fast navigation through any document Go to page β€” jump directly to any page with a single tap Page indicator β€” always know where you are with a subtle page counter overlay No sign-in required. No subscriptions. No ads. Just your PDFs, exactly where you left them.

Screenshots

ReadSync4 screens
Red PDF Reader4 screens

Verdict

The call

The clearest difference is in-app purchases: Red PDF Reader at none against ReadSync's 1. On price, ads, device support and iOS requirement there is nothing between them.

Scored on Price Β· Rating Β· Positive reviews Β· Number of ratings Β· Update frequency Β· Ads Β· In-app purchases Β· Monetization Β· Best chart rank Β· Devices Β· Requires iOS

CostPrice Β· In-app purchases Β· Ads Β· Monetization

Both are free to download. ReadSync sells 1 one-off in-app purchase. Red PDF Reader asks for nothing beyond the download.

Scorecard1 real difference Β· 5 level
ReadSync versus Red PDF Reader: the parameters behind the verdict, then further details
ParameterReadSyncRed PDF Reader
PriceFreeFree
Update frequencyβ€”Every 4 days
AdsNoNo
In-app purchasesYesNo β€” better
DevicesiPhone, iPad, Mac β€” betteriPhone, iPad
Requires iOS18.018
Further details β€” not scored
Size4 MB4 MB
Age rating4+4+
DeveloperAlper AlbayrakKhurshed Gulov

In-app purchases

1 purchases

ReadSync

One-time1
  • Unlock Pro$19.99
None

Red PDF Reader

No in-app purchases

Questions

Is ReadSync free?
ReadSync is free to download, with in-app purchases available.
Is Red PDF Reader free?
Red PDF Reader is free to download, with no in-app purchases.
Do ReadSync or Red PDF Reader have ads?
Neither ReadSync nor Red PDF Reader shows ads.

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