Best Apps for Reading PDF Books on iPhone and iPad (2026)

Quick answer: For reading a PDF book cover to cover, keeping your place across an iPhone and an iPad, and keeping PDFs and ebooks on one shelf, justRead is my pick, and it is the only app here that exports the highlights you make inside a PDF straight to Readwise and Markdown. If you need to mark up pages with an Apple Pencil, fill in a form or sign something, this is the wrong article and PDF Expert, GoodNotes or Notability are the right tools. If your problem is a dense A4 page that is unreadable on a phone, what you want is reflow, sold as "Reading Mode" in PDF Expert and Documents by Readdle, "Liquid Mode" in Adobe Acrobat Reader, and "PDF Reflow" in GoodReader. justRead does not reflow PDFs. Apple Books is free, already installed, and fine for a handful of files, but it falls apart as a PDF library.

Almost every "best PDF reader for iPhone" list ranks document-processing tools: annotate, edit, merge, sign, fill forms, OCR, redact, convert. Those are the right criteria for contracts and school forms, and the wrong ones entirely if your PDFs are books.

Reading a 400-page PDF is a different job. It should reopen where you left off on whichever device you picked up, be findable again in three weeks, let you get a passage out into your notes, and stop a white scanned page from burning your eyes at night. The mainstream roundups score none of that, which is why this list scores nothing else.

Every price and capability below was checked against the vendor's own documentation, help center or App Store listing on 17 August 2026, and where I could not confirm a figure I say so rather than guess. I make justRead, the first app on this list, so read this as a maker's field guide, not a neutral review.

How I judged these apps

Six things: a real library rather than a file list; reading position that survives a cold launch and follows you to your other device; highlights that can leave the app; dark mode that survives a white background baked into the page; whether your ebooks live there too; and whether a large library can get in without a cable. Excluded on purpose: merging, page reordering, form filling, signing, redaction and OCR quality. Real needs, just not reading.

Quick comparison: reading PDF books on iPhone and iPad

Kindle, Google Play Books, Documents by Readdle and Adobe Acrobat Reader are covered below, outside the table.

1. justRead: best for reading PDF books alongside your ebooks

justRead treats a PDF as a book rather than a document. It opens in the same library as your EPUBs, comics and audiobooks, with a PDF badge on the cover and a format filter when you want to see only PDFs. Files arrive from the Files app, by dragging them onto the app on iPad, or from an OPDS catalog, and password-protected PDFs open once you type the password. The reader gives you paginated or continuous scroll, a vertical or horizontal scroll axis, page fit options, a two-page spread with an offset first page, and spacing control. Your position survives a cold launch and catches up to the furthest page you reached on another device.

Two things separate it for book-length reading. First, highlights in a PDF are identical to highlights in an EPUB: six colors, one of them a red underline, a full note editor, and a per-book list of everything you marked, and those highlights export to Readwise, Markdown and PDF. As far as I can find, no other iOS reading app does that for highlights made inside a PDF, so it gets its own section below.

Second, color inversion. A PDF carries a white page inside the file, so an app's dark mode leaves you staring at a bright rectangle in a dark room. justRead inverts the PDF itself, which is what makes a scanned book readable at night. PDFs also carry editable metadata (title, authors, series, series index, tags), because a coverless PDF is an unidentifiable gray tile in every other library. They sync alongside EPUBs through Calibre Content Server, count toward reading statistics and streaks, and the 20-20-20 eye-break timer runs in the PDF reader.

Best for: readers whose PDFs are books, manuals and long reports, who also read EPUBs, and who want their quotes to end up somewhere other than the app.

Trade-offs, and they are real: no Apple Pencil or freehand ink markup, no drawing, no form filling, no signing, no page editing, reordering or merging. No text reflow or reading mode. No page thumbnail grid for PDFs (that is a comics feature). Read-aloud works on EPUB only. iPhone and iPad only, no Mac, Android or desktop version. A free 14-day trial with no account, then $4.99/month, $29.99/year, or $79.99 once for lifetime access. More detail is on the PDF book reader page, and the setup mechanics are in how to read PDFs on iPhone and iPad.

2. Apple Books: the free default, and exactly where it breaks

Apple Books is already installed, free, syncs across your Apple devices, and for a dozen PDFs it is genuinely fine. It breaks in four documented places:

• You cannot change the font size of a PDF. That much is the format, not Apple's fault, but Books has no reflow to work around it either, so on an iPhone your only lever is pinch-to-zoom and panning.
• Highlights on PDFs are not portable. Books gives you Apple's Markup tools (a pen) rather than selection-based text highlights, and Readwise's own documentation states that Apple Books does not create "real" highlights on PDFs according to the PDF spec, so you need a different app. Quotes marked in Books are stuck there permanently.
• The library does not scale. Collections stay flat and manual, and PDFs usually have no cover, so past a few hundred files your shelf is a wall of near-identical gray thumbnails.
• Search is store-first. Users repeatedly report that searching in Books surfaces things to buy rather than the document already in their library.

3. PDF Expert by Readdle: the right answer for reflow and markup

If your complaint is "the text is too small and I am tired of zooming", PDF Expert is the answer, not a reading-first app like mine. Its Reading Mode rebuilds a PDF's text into a single adjustable column with font size control, Day, Night, Sepia and Auto themes, and header and footer cropping. Readdle's help center notes Reading Mode is available on iPhone only, so on an iPad you are back to the page as laid out. It is also a full editor: Pencil annotation, page editing, form filling and signing.

Its weakness for book-length reading is that it is a document tool: a file browser rather than a library, no ebook support, and no route for highlights beyond the annotations inside the file, which you can email onward, including to Readwise.

Pricing, honestly: free to download with paid tiers, and I could not verify a single stable US price. Readdle's pricing page localizes (it served me Czech prices), and the App Store listing shows in-app purchases between $9.99 and $79.99. Check the price in your own region.

Documents by Readdle is the same company's free file manager with the same Reading Mode, and Readdle's documentation for Documents says it works on iPhone and iPad both, which makes it the cheapest way to find out whether reflow solves your problem before paying for anything. It is still a file manager with a viewer attached: no reading library, no highlight export.

4. GoodReader: the power user's file cabinet

GoodReader is what forum threads still recommend when someone turns up with 800 MB textbooks: very large files, genuinely nested folders, strong text search and local Mac sync. It also has PDF Reflow, which GoodReader describes as extracting a page's plain text so you can read it at any size without side-scrolling, and calls experimental, with the caveat that correct extraction is not always possible.

On the US App Store it is $5.99 up front, with an optional Pro Pack ($2.99/month, $17.99/year or $79.99 once) and a separate $9.99 Auto Sync unlock. It was updated within the last week at the time of writing, worth noting in a category full of abandonware. Its weakness is that a file cabinet is not a bookshelf: no covers, no series, no ebooks, no highlight export beyond the file itself.

5. Highlights: for research papers and citations

Highlights is built for academic PDFs on Mac, iPad and iPhone: annotate, then extract those annotations, plus images, tables and citations, into notes you export elsewhere. Its pricing page lists a capable free tier (reading and annotation, PDF metadata editing, scanning and OCR, dark mode, exporting notes as PDF, sorting annotations by color), with Highlights Pro at $4.99/month or $29.99/year.

If citations are the point, a reference manager beats every app here. Zotero, Papers and Paperpile do DOI lookup, BibTeX and shared libraries, none of which justRead has or should pretend to have. Use one when the citation graph is the deliverable, and a reading app when you just want to read the PDFs and keep the quotes.

6. Adobe Acrobat Reader: awkward files, and Liquid Mode

Acrobat Reader is free and renders files that trip up smaller apps. Its Liquid Mode reflows a PDF for a phone screen, and Adobe's documentation lists real limits: it does not apply to files over 200 pages, over 10 MB, or to scanned images of text. That rules out a large share of actual PDF books, so check your file first, and treat the numbers as current-as-documented, because Adobe has moved them before. Heavy, account-driven, and no reading library.

7. Kindle and Google Play Books: if your library already lives in a store

Both are free and both accept your own PDFs. With Send to Kindle, a file sent as-is keeps its fixed layout, and asking Amazon to convert it is what makes the text reflow, with quality depending on how simple the original layout is. Google Play Books takes EPUB and PDF uploads, with documented limits of 100 MB per file, 1,000 files, and no DRM. Both give free cross-device sync, one-file-at-a-time importing, and a store's library rather than tools for your own collection.

8. If you need an Apple Pencil: GoodNotes, Notability, LiquidText

If your PDFs are lecture slides you write on, or a textbook you annotate in the margins, none of the reading-first apps above are for you, justRead included. GoodNotes and Notability are the standard picks, and LiquidText is the one for pulling excerpts out of a long document into a workspace. All three have free tiers and paid upgrades whose prices have changed repeatedly, so I am not quoting a number I cannot stand behind.

Getting your PDF highlights out into your notes

Search for how to get PDF highlights into Readwise and every result is vendor documentation. Readwise's documented routes are to email the highlighted PDF to add@readwise.io (under 30 MB of attachments per email), to use the PDF Import option on its website, or to read inside Readwise Reader, and it notes that its support for PDF highlights is "in perpetual beta". BookFusion says exports can only be done from its web app, and Apple Books highlights cannot get there at all. All of it involves leaving your phone.

In justRead the flow is on the device, and it is the same for a PDF as for an EPUB:

1. Select the text on the page and pick one of six highlight colors, one of which is a red underline. Tapping cycles the colors, so there are no menus.
2. Add a note if you want to catch the thought while it is fresh. The note travels with the highlight everywhere it goes afterwards.
3. Open that book's highlights list, which collects every highlight and note from the PDF in one place.
4. Export. One tap sends every highlight from the book to Readwise with its title, author, page and your notes. The same set exports to Markdown, which drops straight into Obsidian, Notion or any other notes app, or to PDF for an archive copy.

Connect Readwise once and that is the setup. The same paths work for EPUBs, covered on the highlights export page. One caveat applies everywhere: this needs selectable text, and a scanned page has none.

How to give your PDFs a real library on an iPad

The default state of PDFs on iOS is a pile in Files, sorted by filename, mostly called things like 9781234567890_ch04_final(2).pdf. Three moves fix that.

Put them in an app that has a library. Covers, tags, series and collections are what let you find something three months later. In justRead, PDFs land on the same shelf as EPUBs with a PDF badge and a format filter. More on organizing at scale on the ebook library page.

Fix the metadata at import. Most PDFs have no cover and a garbage embedded title, so editing title, authors, series, series index and tags turns an anonymous tile into something you recognize. Five seconds per file saves an hour of hunting later.

Bring them in in bulk. Drag and drop is fine for a handful; for a whole collection, use an OPDS catalog or a Calibre server.

How to read a scanned PDF, and what it costs you

A scanned book is a stack of page images. It looks like text and behaves like a photograph. Test any file by trying to select a line. If nothing selects there is no text layer, and four things follow: search finds nothing inside it, in any app; you cannot make text highlights, because selection has nothing to grab; reflow is impossible, which Adobe says outright for Liquid Mode and is equally true of every other Reading Mode; and read-aloud cannot read it.

The fix is OCR, which analyzes the images and writes a text layer into the file. Highlights lists scanning and OCR in its free tier, and Acrobat and PDF Expert include OCR in paid tiers. Run it once and the file behaves normally afterwards. What still works without OCR: page navigation, reading position, two-page spreads, and, for old library scans, color inversion for reading at night.

Is converting a PDF to EPUB worth it?

Sometimes, and it depends entirely on the layout.

It works when the PDF is born-digital rather than scanned, single-column and mostly prose: a novel, an essay collection, a plain report, most public-domain material. Calibre converts these acceptably, and the result reflows and takes a font size like a real ebook.

It goes badly when the file is a two-column academic paper, a textbook, anything heavy with figures, tables, equations or footnotes, or anything scanned. Columns interleave into nonsense, tables collapse, captions detach from figures, and you go back to the PDF anyway.

The better move, when it exists: find the EPUB of the same book instead of converting. A publisher's EPUB beats a converted PDF every time, and the trade-offs are worth understanding first, which is what EPUB vs PDF for reading covers.

How to sync a Calibre PDF library to an iPad

If your collection already lives in Calibre, this is the least painful path onto a tablet, and it carries PDFs, not only EPUBs. Turn on the Calibre Content Server on the machine holding the library, keep both devices on the same network, and connect from the app. justRead syncs PDFs alongside your EPUBs, with reading progress kept in step rather than a one-time copy. The walkthrough is on the Calibre sync page.

Worth knowing: Apple removed Calibre's USB device sync on iOS, so the cable route is gone. What remains is the network, a cloud folder, or an OPDS catalog, which also works with self-hosted servers like calibre-web, Komga and Kavita.

What none of these apps can do

Nobody reflows a scanned PDF, because there is no text to reflow. No Reading Mode makes an A4 page genuinely comfortable on a phone either, because it is a reconstruction, and figures, tables and equations are what it drops. And highlights only move between apps when they follow the PDF spec and live inside the file, so choose the app you highlight in before you mark up 200 pages, not after.

Which one should you pick?

If your PDFs are books you want to read properly, keep on one shelf with your ebooks, keep your place in across two devices, and pull quotes out into your notes, that is what justRead is built for, with the honest cost that it will never mark up a page with a Pencil or reflow a column for you. If any of those clauses does not describe you, one of the other apps here does, and the quick answer at the top says which.

Frequently asked questions

What is the best app for reading PDF books on an iPad in 2026?
For reading end to end and keeping PDFs on the same shelf as your ebooks, justRead. For reflow on a phone, PDF Expert. For Apple Pencil markup, GoodNotes or Notability. For very large files, GoodReader. Apple Books is a fine free default.

Can I keep PDFs and EPUBs in one library?
Yes, in justRead and in Apple Books. justRead adds a format filter and editable metadata so a coverless PDF is identifiable. PDF Expert, GoodReader and Highlights are PDF-only.

Will an app remember my page in a PDF and carry it to my other device?
justRead saves your position across a cold launch and catches up to the furthest page reached on another device, and Apple Books syncs your place across Apple devices. PDF Expert, GoodReader and Highlights reopen where you stopped on the device you used.

Can I export PDF highlights to Readwise or Obsidian?
From justRead, yes: to Readwise with one tap, to Markdown for Obsidian, or to PDF. From Apple Books, no, because Readwise's documentation says Books does not create spec-compliant PDF highlights. Elsewhere, email the annotated file to add@readwise.io or upload it on Readwise's website.

Why can I not change the font size of a PDF in Apple Books?
A PDF has a fixed page size, so there is no text to resize, only a page to zoom, and Books has no reflow. Apps with a Reading Mode (PDF Expert, Documents) or Liquid Mode (Acrobat) rebuild the text into a resizable column instead. justRead does not.

Do I need an Apple Pencil to highlight a PDF?
No. Text highlighting is selection-based and works with a finger. A Pencil is only needed for freehand ink markup, which justRead does not have at all.

Can justRead read a PDF aloud?
No. Read-aloud works on EPUB files only.

Can I open a password-protected PDF?
Yes, it opens once you type the password.

Is justRead free?
A 14-day free trial with no account, then $4.99/month, $29.99/year, or $79.99 once for lifetime access. iPhone and iPad only, with no Mac, Android or Windows version.

Next, see how to read PDFs on iPhone and iPad for the step-by-step setup, EPUB vs PDF for reading if you can choose your format, or the PDF book reader page for the PDF side of justRead in detail. You can also browse all of our reading guides and comparisons.