Best PDF Markup and Annotation Apps for iPad and Apple Pencil in 2026

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Apple Preview is now the best free starting point for PDF markup on an iPad. With iPadOS 26, it can highlight, underline, draw with Apple Pencil, fill forms, add signatures and text boxes, rearrange pages, scan documents, create searchable PDFs, and password-protect files. You only need another app when your workflow goes beyond basic markup.

For a serious PDF-first workflow, choose PDF Expert. For handwritten study notes, choose Goodnotes; for lectures or meetings with synchronized audio, choose Notability. Researchers should look at LiquidText or MarginNote 4, while professionals handling formal review may prefer Adobe Acrobat or Foxit. Technical drawing and measurement work is better suited to Drawboard PDF, and Xodo is a practical mixed-device option.

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The important distinction: PDF editor, notebook, or research workspace?

There is no universally best iPad PDF annotation app. The right choice depends on what the PDF represents in your workflow.

• A finished document: Use a PDF-first app such as Preview, PDF Expert, Acrobat, Xodo, Drawboard, Foxit, or PDFgear. These are the better choices for forms, signatures, page management, redaction, professional comments, and sending a conventional PDF to another person.
• A background for handwritten notes: Use Goodnotes or Notability. These apps import PDFs into a notebook, where you can add pages, templates, handwriting, audio, and study material.
• A source for research: Use LiquidText or MarginNote. Their value lies in pulling excerpts from several documents, connecting ideas, building maps, and turning highlights into notes or flashcards.

This distinction also answers an important compatibility question: PDF-first apps generally keep the PDF as the main document, while notebook and research apps may keep your work in an app-specific library until you export it.

What changed in 2026: Preview is now on iPad

Older comparison articles often recommend third-party apps because iPad had no dedicated Preview application. That advice is now outdated. Under iPadOS 26, Apple provides Preview for viewing and working with PDFs and images on iPad.

Apple documents support for selecting and copying PDF text, highlighting, underlining, strikethrough, freehand Apple Pencil markup, shapes, stickers, text boxes, signatures, interactive form filling, page insertion and deletion, page rotation and cropping, scanning, searchable PDF creation, sharing, printing, and password protection. See Apple’s guides for PDF annotation and editing, scanning and searchable PDFs, and form filling.

Preview does not make third-party apps obsolete. It is still a native utility rather than a full research system, enterprise review platform, technical markup library, or advanced text-and-image PDF editor. But for circling a paragraph, signing a form, filling a field, or writing a quick note before sending a file back, it should be the first app you try.

At-a-glance comparison

App	Best for	Workflow type	Free essentials	Main limitation
Preview	Quick markup, forms, signatures, scanning	PDF-first	Yes, with iPadOS 26	Limited research, collaboration, and advanced editing
PDF Expert	Apple-focused professional PDF work	PDF-first	Basic reading and markup; advanced tools paid	Subscription for many advanced features; Apple-centric
Goodnotes	Handwritten study notebooks	Notebook-first	Limited free plan	Export and notebook structure may not preserve every PDF feature
Notability	Lectures and meetings with audio	Notebook-first	Starter plan	More note-centric than a full PDF editor
LiquidText	Excerpts and multi-document research	Research workspace	Limited free access; advanced plans available	Steeper learning curve
MarginNote 4	Highlights, mind maps, flashcards	Research and study workspace	Plan-dependent	Complex and specialized
Adobe Acrobat	Formal review, forms, Adobe workflows	PDF-first	Viewing, annotation, signing, printing, searching, sharing	Advanced editing and document tools require a paid plan
Xodo	Cloud files and mixed-device work	PDF-first	Core tools; advanced tools vary by plan	Feature availability depends on subscription
Drawboard PDF	Technical drawings and pen markup	PDF-first	Basic ink, review, signatures, and page tools	Advanced tools and cloud features are paid
Foxit PDF Editor	Business forms, security, and XFA	PDF-first	Basic reading and annotation	Advanced editing, OCR, and security features require a subscription
PDFgear	Feature-rich free markup	PDF-first	The current iOS listing says its tools are free	Privacy and long-term product certainty deserve scrutiny

Every app in the table supports Apple Pencil writing in some form, but that does not mean every app supports the same Pencil features. Pressure, hover, tilt, double-tap, squeeze, barrel roll, palm rejection, and eraser behavior depend on the Pencil model, iPad hardware, operating system, and the app’s implementation.

1. Apple Preview: the best free starting point

Choose Preview when you occasionally need to mark up a PDF, complete a form, add a signature, scan paper, or send a corrected document. It is especially attractive because it requires no separate PDF subscription and fits naturally with Files and the rest of the iPad system.

What Preview can do

• Open, read, search, select, and copy PDF text.
• Highlight, underline, or strikethrough selected text.
• Draw or write with Apple Pencil or a finger.
• Add text boxes, shapes, stickers, and signatures.
• Fill interactive PDF forms.
• Scan paper documents and create searchable PDFs.
• Insert, delete, move, rotate, and crop pages.
• Lock PDFs with a password.
• Share or print the marked-up file.

Basic Preview workflows

To highlight text: Open the PDF in Preview, drag across the text, tap Highlight, and choose highlighting, underlining, or strikethrough. Apple documents this workflow in its Preview guide.

To write or draw: Open the PDF, tap Markup, choose a pen, marker, pencil, shape, or another tool, and write with Apple Pencil or your finger. Use Undo when needed. The general Apple Pencil markup controls are also described in Apple’s guide to writing and drawing in documents.

To add text or a signature: Tap Markup, tap Add, then choose Add Text or Add Signature.

To fill a form: Open the form and tap the Form Fill button. Tap a blue field, type or select an autofill suggestion, and use Add if you need to place a signature or text box manually. A static form without interactive fields may require those text boxes rather than normal field entry.

Where Preview stops

Preview is not designed as a literature-review canvas, audio notebook, flashcard system, reusable technical-symbol library, or formal team review service with detailed reviewer attribution and revision tracking. Those are editorial limitations inferred from Apple’s documented feature set, not claims that Apple describes Preview as incapable of every possible workflow.

Verdict: Start with Preview unless you already know you need OCR-heavy editing, advanced redaction, multi-document research, extensive handwriting organization, or collaboration.

2. PDF Expert: the best PDF-first all-rounder for Apple users

PDF Expert is the strongest general recommendation when the PDF itself must remain the central, shareable document. It goes well beyond drawing on a page without becoming a notebook or research system.

What it adds beyond Preview

• Text and image editing.
• Page insertion, deletion, rotation, rearrangement, merging, and splitting.
• Interactive form filling and e-signatures.
• OCR for scanned documents.
• Conversion to and from Word, Excel, PowerPoint, images, and text.
• Password protection and permanent redaction tools.
• Notes, stamps, stickers, drawings, and audio notes.
• Construction tools including scale, measure, polygon, polyline, and redline tools.
• Synchronization across Apple devices.
• PDF Copilot features for summaries, questions, explanations, and document analysis.

Its annotation feature page and App Store listing document these capabilities. The exact availability of OCR, conversion, redaction, AI, and advanced editing depends on the current plan.

Pricing and trade-offs

The current US pricing page lists $4.99 per week, $79.99 per year, and a $139.99 lifetime option described there as Mac-only. App Store prices, taxes, student offers, billing channels, and regional plans can differ, so verify the purchase screen before subscribing. Do not assume that a lifetime purchase shown on the website is automatically a lifetime iPad purchase.

PDF Expert is overkill for someone who only signs one form every few months. Its strongest cross-device experience is also Apple-centric, so a Windows- or Android-heavy team may be better served by Acrobat, Xodo, Foxit, or Drawboard.

Verdict: Choose PDF Expert when you need a polished iPad PDF editor for editing, organizing, signing, OCR, redaction, or professional handoff.

3. Goodnotes: best for handwriting-heavy study

Goodnotes treats an imported PDF as part of a notebook. That is precisely why it works so well for students: lecture slides, reading assignments, handwritten explanations, templates, and extra blank pages can live together.

Goodnotes is a strong fit for

• Writing extensively on lecture slides or worksheets.
• Adding handwritten pages around a PDF.
• Keeping class materials and study notes in one organized library.
• Searching recognized handwriting later.
• Using templates and combining source material with personal notes.

Goodnotes can import PDFs, images, Word files, and PowerPoint files on supported Apple platforms. When preserving layout matters, importing a PDF version is safer than importing an Office file directly; Goodnotes notes that Office-file conversion can change layout. See its import guidance.

The export choice matters

Goodnotes offers Editable PDF and Flattened PDF export:

• Editable PDF: keeps objects selectable and preserves document outlines and original hyperlinks, but handwriting is not searchable.
• Flattened PDF: is generally more compatible and can make handwriting searchable when handwriting recognition is enabled, but document outlines and original hyperlinks are not preserved in the same way.

These are not interchangeable. Use editable export when the recipient needs to work with objects and links. Use flattened export when the visual appearance must survive opening in different PDF viewers. Goodnotes explains the distinction in its documentation on editable and flattened PDFs.

If the exported file loses writing or the page background, start the export again and enable Include Page Background and Include Annotation. Goodnotes documents this recovery step here.

Plans

The current plan structure includes a free tier limited to three files, a 5 MB import limit, watermarked exports, and a 20-minute audio limit. Essential provides unlimited documents and additional note-taking, transcription, and collaboration features. Special Edition is a one-time Apple-platform purchase, while Pro expands AI and productivity features; AI Pass is a separate paid AI add-on. Plans and prices vary by region and purchase channel, so check Goodnotes’ current plan documentation.

Verdict: Goodnotes is better than a conventional PDF editor when your goal is to study by writing. It is not the best choice for advanced PDF production, native business comments, redaction, or document comparison.

4. Notability: best for notes synchronized with audio

Notability’s audio-linked notes are its defining advantage. You can record a lecture or meeting and later jump through the recording by tapping the point at which a note was written.

It imports PDFs, PowerPoint files, spreadsheets, images, and documents. With Apple Pencil, you can handwrite, highlight, draw shapes, erase, select, type, and add media. It supports PDF outlines and exports to PDF, image, or native-note formats. Real-time collaboration is available on supported cloud plans; its model is more like collaborative notes than a conventional Acrobat review workflow.

The current US-facing pricing page lists Starter as free, Plus at $15.99 per year, Pro at $79.99 per year, Business at $60 per user per year, and Business Pro at $180 per user per year. Regional prices, taxes, platform, and plan availability can differ; see the current pricing page.

Notability’s import warning

Notability documents that annotations created by some other PDF applications may not display correctly after import. If marks are missing, create a flattened copy in Acrobat or PDF Expert and import that version. For Office-file import problems, convert the file to PDF through Pages, Keynote, or Numbers. For very large documents, compress or split the PDF into smaller sections. Notability lists these steps in its annotation troubleshooting and import-error guidance.

Verdict: Choose Notability over Goodnotes when synchronized audio is central. Choose Goodnotes when handwriting organization and notebook flexibility matter more than recording.

5. LiquidText: best for deep research

LiquidText is built for extracting and connecting ideas rather than simply writing in the margin. You can place excerpts from a PDF into a workspace beside the source, connect notes and passages with ink links, compare distant pages, and work across multiple documents.

Why researchers choose it

• Pull excerpts into a separate workspace while retaining source context.
• Connect notes, excerpts, pages, and documents with links.
• Compare several papers, reports, or legal documents.
• Search, bulk-highlight, tag, and link passages.
• Import web pages through Safari and work with PDF, Word, and PowerPoint files.
• Use OCR for scanned documents.
• Import from Zotero and Mendeley on supported plans.
• Export research results to PDF or Word.

LiquidText is available across Apple platforms, with the current App Store listing requiring iPadOS 17.6 or later on iPad, iOS 17.6 or later on iPhone, macOS 13.5 or later on Mac, and visionOS 1.3 or later on Apple Vision. The US listing currently shows LiquidText Live at $10.90 monthly and $99.99 yearly, alongside student and upgrade prices. Check the current App Store listing before publication or purchase.

Verdict: LiquidText is the best fit when the question is “How do these documents relate?” rather than “Which pen should I use to mark this page?” Its project model takes longer to learn and its research workspace is not the same as a normal PDF for a recipient to edit.

6. MarginNote 4: best for turning reading into a study system

MarginNote 4 connects PDF highlights and excerpts to notes, mind maps, flashcards, OCR, spaced repetition, cross-document links, study sets, and bidirectional source links. Its central appeal is that one excerpt can become a highlight, a mind-map node, and a flashcard.

That makes it particularly suited to law, medicine, graduate study, exam preparation, and long-term knowledge management. It supports Apple Pencil and iCloud synchronization across iPhone, iPad, and Mac, although access to Mac features and advanced OCR or AI depends on the plan.

The official pricing page currently lists Pro Lifetime at $12.99 for iPhone and iPad, Max Annual at $16.99 per year, and Max Lifetime at $51.99. Regional App Store prices may differ, and the Max plans include Mac access and advanced OCR/AI features. See MarginNote’s pricing page and the current App Store listing.

Verdict: Choose MarginNote when annotations should become a reusable study database. If you simply want to highlight a textbook and send it back, Preview or PDF Expert will be easier.

7. Adobe Acrobat: best for formal review and Adobe ecosystems

Acrobat Reader can be used free for opening, viewing, signing, printing, annotating, searching, and sharing PDFs. Its mobile annotation tools include highlights, underlines, strikethroughs, sticky notes, text comments, freehand drawing, replies, and shared review workflows.

Shared-review comments require signing in with an Adobe ID to add, edit, or delete comments. Adobe also documents offline editing that synchronizes after reconnection in supported review workflows. Premium mobile tools add PDF creation, export, modification, combining files, page organization, compression, password protection, and additional editing or OCR depending on the plan.

Acrobat is the sensible choice when clients, colleagues, or an organization already use Adobe, or when the workflow involves formal review, forms, OCR, redaction, security, comparison, and document governance. It is less compelling for a student who only wants a comfortable Apple Pencil notebook.

Verdict: Choose Acrobat for compatibility with Adobe-heavy organizations and formal document review, not because every advanced feature is free.

8. Xodo: best for mixed-device and cloud-oriented workflows

Xodo is a useful middle ground for people who move between iPad and other platforms or keep documents in several cloud services. Its iPad app lists annotation and drawing, highlighting, links, stamps, images, page insertion and deletion, rotation, cropping, splitting, extraction, form filling, signatures, scanning, search, tabs, and Apple Pencil support.

It integrates with iCloud, OneDrive, Google Drive, and Dropbox. OCR options, flattening, PDF conversion, compression, and other advanced tools are subject to the current plan structure. Xodo’s own mobile guide specifically describes Apple Pencil annotation and writing.

Verdict: Xodo is a strong practical alternative to Acrobat or PDF Expert when cloud storage and mixed-device access matter more than an Apple-only library.

9. Drawboard PDF: best for technical drawings and pen-first markup

Drawboard PDF emphasizes pressure-sensitive Apple Pencil ink, freehand drawing, highlights, shapes, comments, signatures, reusable Markup Library items, measurements, areas, polylines, and calibration. That combination makes it particularly useful for architects, engineers, contractors, inspectors, and anyone reviewing plans or specifications.

Drawboard also promotes cross-platform access across iOS, macOS, Windows, Android, and the web. Its Store+Share service provides synchronization and sharing, but that is a different workflow from saving a PDF directly in Files or iCloud Drive.

The current Basic plan includes essential tools, text review, digital ink, shapes and images, bookmarks, search, annotation flattening, signatures, notes, and basic page insertion, rotation, and deletion. The pricing page says paid features are subscription-only. Because Drawboard’s pages and third-party listings have shown different tier names and prices over time, check the current pricing page and iPad purchase sheet rather than relying on an old roundup.

Verdict: Pick Drawboard when measurement, reusable symbols, and technical pen markup are more important than study features.

10. Foxit PDF Editor: a credible business alternative to Acrobat

Foxit PDF Editor targets business PDF work. Its iPad listing includes annotations and stamps, text and image editing, page reorganization, forms, XFA forms, handwritten signatures, redaction, password protection, cloud services, tabbed documents, reflow, and read-aloud modes.

OCR and handwritten-note conversion are available on subscription tiers, as are AI features such as document summaries, translation, document chat, and writing tools. Foxit’s documentation also describes Apple Pencil double-tap behavior for switching between the Pencil tool and eraser in supported configurations.

Foxit is worth considering when your work involves business forms, XFA forms, security, Windows compatibility, or an organization that already uses Foxit. It is not a notebook app, and advanced editing, OCR, redaction, and conversion are not necessarily included in the free download.

Verdict: Foxit is a strong Acrobat alternative for business-oriented PDF workflows, especially forms and security.

11. PDFgear: the feature-rich free alternative

PDFgear is worth testing if you want more page management and editing than Preview offers without immediately paying for a subscription. Its current US App Store listing describes PDF viewing and printing, highlighting, underlining, strikethrough, text insertion, shapes, arrows, ink writing, erasing, page insertion, deletion, rotation, extraction, form filling, signatures, stamps, iCloud storage, PDF translation, and Apple Pencil improvements.

The listing says its iOS functions are free without trial watermarks or page-count limits. That is a current store-listing claim rather than a permanent guarantee; verify it before relying on the app for an important workflow.

Privacy deserves separate attention. The App Store privacy section says the developer’s stated practices may involve data handling and notes that the information has not been verified by Apple. That does not prove that PDFgear is unsafe, but it does mean you should not describe it as private or the safest free option without additional privacy research.

Verdict: PDFgear is a compelling free third-party option, particularly for basic editing and page operations, but scrutinize its privacy terms before using confidential documents.

Which app should you choose?

Your situation	Best first choice	Why
You occasionally circle, highlight, sign, or fill a PDF	Preview	It now covers the basic workflow without another subscription.
You need to edit text, rearrange pages, OCR, sign, or redact	PDF Expert	Broad PDF-first tools in an Apple-oriented interface.
You annotate lecture slides and write many handwritten notes	Goodnotes	Notebook organization and handwriting are the center of the experience.
You need the recording connected to your notes	Notability	Audio playback can return to the point where notes were made.
You compare papers and collect source-linked excerpts	LiquidText	Its workspace is designed around relationships between passages and documents.
You want highlights to become mind maps and flashcards	MarginNote 4	It connects reading, structured notes, and spaced repetition.
You work in Adobe-based review teams	Adobe Acrobat	Comments, shared review, forms, and Adobe compatibility are the priority.
You use iPad alongside Windows or Android	Xodo	Cloud integrations and mixed-device support are central strengths.
You mark up plans, drawings, and specifications	Drawboard PDF	Measurements, reusable markups, and pen-first tools fit technical work.
You need business forms, XFA, and Foxit compatibility	Foxit PDF Editor	It is built around business PDF features rather than notebook notes.
You want a free third-party feature set	PDFgear	Its current iOS listing includes a broad set of free tools, subject to change.

Independent reader supportYour contribution helps us test, update, and keep practical guides available for everyone.Support on Ko-Fi

Apple Pencil and iPad compatibility

Do not buy an Apple Pencil based only on the iPad’s marketing name. Apple’s current compatibility matrix distinguishes Pencil generations and iPad models.

• Apple Pencil Pro: compatible with iPad Pro M4/M5, iPad Air M2/M3/M4, and iPad mini A17 Pro models listed by Apple.
• Apple Pencil USB-C: compatible with current USB-C iPads and many earlier iPad Pro, Air, and mini models.
• Apple Pencil 2: compatible with selected iPad Pro, iPad Air, and iPad mini models.
• Apple Pencil 1: compatible with older iPad, iPad mini, iPad Air, and iPad Pro models; an adapter is required with some USB-C iPads.

Apple’s current iPadOS 26 compatibility page lists iPad Pro 11-inch first generation and later, iPad Pro 12.9-inch third generation and later, 13-inch M4/M5 iPad Pro, iPad Air third generation and later including M2, M3, and M4, iPad eighth generation and later including A16, and iPad mini fifth generation and later including A17 Pro. Features can vary by model, region, language, and app version; consult Apple’s current compatibility list.

Apple Pencil Pro features such as squeeze, barrel roll, hover, double-tap, and pressure response are not automatically available in every app. Pencil writing itself is a much broader form of support than full implementation of every Pencil gesture.

PDF interoperability: the part most comparisons omit

Before choosing a notebook or research app, decide where the final file must open. A marked-up document that looks perfect inside an app is not necessarily equivalent to a conventional PDF that behaves identically in Preview, Acrobat, Windows, or a browser.

Editable versus flattened output

• Editable output keeps annotations or objects available for further selection and editing. It is useful when the next person needs to continue reviewing the file, but unsupported annotation types may render differently elsewhere.
• Flattened output incorporates the visible result into the page appearance. It is usually the safer choice for visual compatibility, but it can remove editability, outlines, hyperlinks, or object-level information.

Goodnotes explicitly documents this trade-off. Notability also documents cases in which annotations from other PDF apps do not appear after import and recommends flattening in Acrobat or PDF Expert. In either app, keep the original notebook or project as a backup before flattening.

A safe handoff procedure

1. Export the PDF with annotations, page backgrounds, and the desired editable or flattened setting.
2. Open the exported file in a second viewer, preferably Preview and Acrobat if both are available.
3. Check several handwritten marks, text highlights, links, outlines, signatures, and form fields.
4. Only then send the file to the recipient.
5. Keep the original app project if you may need to revise the document later.

For Goodnotes, enable Include Page Background and Include Annotation if the exported file is missing marks or backgrounds. For Notability, flatten annotations in Acrobat or PDF Expert when imported comments are not visible.

Scanned PDFs, OCR, and handwriting search are different things

A text-native PDF contains a text layer. You can usually select words, search them, and apply semantic highlighting. A scanned PDF may be only a page image. You can still draw on it, but normal text selection, search, copy-and-paste, and text highlighting will not work until OCR creates a text layer.

Test these cases separately:

1. A normal text-native article.
2. A scan with no text layer.
3. The same scan after OCR.
4. A complex file with columns, tables, formulas, images, or handwriting.

Preview can create searchable PDFs from scans. PDF Expert, LiquidText, Foxit, and MarginNote document OCR features, but their exact availability depends on the app and plan. Drawing on a scanned page is not evidence that an app can semantically highlight or search the scan.

Forms, signatures, and redaction

These tasks are often confused:

• Interactive form filling: typing into fields that already exist in the PDF.
• Static form completion: placing text boxes or a signature on a page that has no interactive fields.
• Handwritten signature: drawing or inserting a signature image.
• Digital certificate signature: a more formal signing method with identity verification and validation requirements.
• Redaction: permanently removing sensitive content, not merely hiding it.

Preview handles interactive fields and added signatures. Foxit specifically lists XFA form support. Acrobat, PDF Expert, Foxit, Xodo, and some Drawboard plans advertise broader business, security, or redaction tools. Verify that the exact iPad version and paid tier support permanent redaction before using an app for confidential information.

A black rectangle drawn over a name is not automatically redaction. If the text can still be selected, copied, searched, or removed, it has probably only been covered. Use a documented redaction tool, then test the resulting file by trying to select and copy the concealed text.

Common problems and fixes

Annotations disappear in another app

Likely causes include a proprietary annotation type, an export completed without annotations, a broken PDF structure, or a receiving viewer that does not support the mark. Reopen the original, export again with annotations enabled, and try a flattened copy for maximum visual compatibility. Confirm the result in Preview or Acrobat before sending it.

The PDF will not import

• Convert Word or PowerPoint to PDF first.
• Save the file to Files and import from there instead of directly from a browser.
• Compress the file.
• Split a large textbook or report into chapters.
• Try a flattened copy.
• Check whether it is password-protected.
• Check available iPad storage and memory.

These are also the remedies Notability recommends for Office-file and large-document import failures.

A static form does not accept typing

Use Preview’s Add Text tool to place text manually, then add a signature. For complex form creation or editing, use a PDF editor such as Acrobat, PDF Expert, Foxit, or Xodo.

Cloud synchronization creates duplicates or conflicts

Choose one source of truth: Files and iCloud Drive, the app’s internal library, a provider such as OneDrive or Dropbox, or a research project database. Avoid editing the same PDF simultaneously in two systems unless the app documents how conflicts are handled. Cloud sync does not automatically mean conflict-free synchronization.

Subscriptions, accounts, offline use, and AI

Free download does not mean every essential feature is free. Check separately for:

• Free annotation and handwriting.
• Free export.
• Free signatures and form filling.
• Page management limits.
• OCR charges or subscription requirements.
• Cloud synchronization and storage limits.
• Collaboration and reviewer accounts.
• AI credits, account requirements, and internet access.

AI is an optional layer, not a requirement for marking up a PDF. Depending on the app and feature, AI may require an account, paid plan, credits, document upload, an internet connection, or supported Apple Intelligence hardware. MarginNote documents on-device Apple Intelligence options for certain features, while PDF Expert, Foxit, Acrobat, and Goodnotes advertise different account- or plan-dependent AI tools. Judge the specific feature rather than assuming that an app’s entire AI system is private or offline.

How to test an app before committing

If the document matters, test the app with the same files you actually use rather than judging it from screenshots. Record your iPad model, Apple Pencil model, iPadOS version, app version, test date, storage location, and whether the device was online.

A useful test pack includes:

1. A text-native article.
2. A scanned PDF.
3. An interactive form.
4. A password-protected document.
5. A PDF with hyperlinks and an outline.
6. A large textbook or technical drawing.
7. A PDF containing existing Acrobat comments.
8. A file with columns, tables, formulas, and images.
9. A document requiring a signature and text boxes.
10. A PDF exported from the app and reopened in Preview and Acrobat.

Check highlight accuracy, Pencil writing, palm rejection, finger scrolling, eraser behavior, undo, text selection, search, OCR, page navigation, export size, link and outline preservation, offline editing, login requirements, and whether the app creates duplicates or proprietary copies. Without a published procedure and results, avoid presenting subjective impressions such as lowest latency or best handwriting as objective benchmarks.

Final recommendations by reader type

• Occasional signer: Preview.
• Student who writes on slides: Goodnotes.
• Student who records lectures: Notability.
• Graduate student or researcher: LiquidText for connected excerpts; MarginNote for flashcards and a structured study system.
• Lawyer or business reviewer: Acrobat, PDF Expert, or Foxit, depending on the organization’s ecosystem.
• Architect, engineer, or contractor: Drawboard PDF.
• Apple-only professional: PDF Expert.
• Mixed-device user: Xodo, Acrobat, Foxit, or Drawboard.
• Subscription-averse user: Preview first, then test PDFgear or the free tiers of Xodo and other apps against your files.
• Privacy-sensitive reader: Prefer local, file-based workflows where possible, disable unnecessary cloud or AI features, and read the app’s current privacy disclosures before importing confidential documents.

Frequently Asked Questions

Can I annotate a PDF on an iPad without buying an app?

Yes. With iPadOS 26, Apple Preview supports text highlighting, underlining, strikethrough, Apple Pencil drawing, text boxes, signatures, form filling, page operations, scanning, and password protection. It is the best first option for occasional markup.

Will Apple Pencil annotations work in Acrobat or Preview on another device?

Usually the visible result can be shared as a PDF, but rendering depends on how the source app exports annotations and how the receiving viewer supports them. For important files, export with annotations included, test an editable and a flattened copy, and reopen the result in Preview or Acrobat before sending it.

What is the best app for annotating lecture slides?

Goodnotes is the strongest general fit for handwriting-heavy slide annotation and notebook organization. Choose Notability instead when synchronized lecture or meeting audio is the deciding feature.

What is the best PDF app for research papers?

Choose LiquidText for extracting and connecting excerpts across multiple papers. Choose MarginNote 4 if you also want mind maps, flashcards, and spaced repetition. Use PDF Expert or Preview when you only need ordinary page-by-page markup.

Can I redact information by drawing a black box over it?

No. A black shape may only cover the text visually while leaving it selectable and copyable. Use a documented permanent-redaction tool in an appropriate paid PDF editor, then test the exported file by selecting and copying the concealed content.

The Bottom Line

Start with Preview. iPadOS 26 now handles the basic PDF jobs that once required a third-party download. Move to PDF Expert when the PDF itself is a professional document; choose Goodnotes or Notability when it belongs inside a handwritten notebook; and choose LiquidText or MarginNote when reading is part of a larger research or study system. Before sharing anything important, verify the export in another PDF viewer—especially when annotations, links, outlines, forms, or redaction matter.

Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.