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A free PDF Expert alternative for iPhone Duo

If you need to read, sign, fill and mark up PDFs, not edit their existing text, PDF Duo does it for free with no subscription, and on iPhone Duo it adds a book spread with a page curl and a laptop pose for signing.

Updated 27 October 2026

Where PDF Expert leads

PDF Expert by Readdle is a full PDF editor. Its yearly plan, the one that covers iPhone and iPad, includes editing PDF text, images and links, converting PDFs to Word, Excel and PowerPoint, and recognising text (OCR), according to pdfexpert.com/pricing on 27 October 2026. PDF Duo does none of those. If you need them, PDF Expert is the better choice.

What PDF Duo does, free

  • Read with search, contents and bookmarks; it reopens where you left off
  • Sign with your finger; saved signatures and initials stay on this phone
  • Fill forms field by field, with Next field
  • Highlight, underline and strike through by dragging; pen, text boxes, notes and shapes
  • Rotate, delete, reorder and extract pages; insert a blank page or a photo
  • Export a flattened copy

No ads, no watermark, no account and no subscription.

On iPhone Duo

Closed, the buttons stand in the Duo’s control column. Open on its side, two pages sit across the fold and turn with a page curl. Half open like a laptop, the page stands above the fold and the signature pad lies flat below.

Private, with no AI and no cloud

PDF Duo has no account, no cloud service of ours and no AI features. Your documents stay in your files, it works offline, and there are no ads and no tracking.

Questions

Can PDF Duo edit the text in a PDF like PDF Expert?

No. PDF Duo signs, fills, highlights, draws, adds text and notes, and reorders pages. Editing existing text or images is not supported yet.

Is PDF Duo really free?

Yes. Reading, mark-up, form filling, signing and flattened export are all free, with no subscription.

Can I use PDF Duo and PDF Expert side by side?

Yes. PDF Duo opens your PDFs where they are, so both apps can open the same files.

Download on the App Store

Free on the App Store. Free · No ads · No watermark · No account