Comparison

AI Viewer vs Nitro PDF Pro

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

Head to head
About

AI Viewer

View Adobe Illustrator (.ai) files on your mobile device without needing a license. Convert .ai files to PDF or PNG, zoom in on previews, and easily locate Illustrator files stored on your device.

Highlights
  • Preview .ai files
  • Save as PDF or PNG
  • List all .ai files on device
  • Pinch to zoom
  • Remove ads permanently
  • Contact support
Features
Read full description

AIViewer app can preview .ai files created using Adobe illustrator. View Adobe illustrator files on your iPhone/iPad without buying costly license. Using AI Viewer, you can do the following - 1. Preview all pages of Adobe illustrator(.ai) files. Language supported : English, Korean, Thai and more are coming soon. 2. Save .ai file as .pdf file or .png image into mobile device. 3. List all Adobe illustrator(.ai) present in mobile device. 4. Pinch to zoom to show large preview. 5. In-app purchases: to remove full page advertisement permanently during application use. 6. Contact Us : In case of any query feel free to contact us at support@magicapps.co.in or use contact us button provided in application. Terms of use(EULA) : https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

About

Nitro PDF Pro

Edit, read, sign, and secure PDF documents on your iOS device. This powerful yet lightweight app allows for on-the-go productivity with features like text editing, annotation, form filling, and cloud syncing.

Highlights
  • Edit PDF text
  • Annotate and highlight PDFs
  • Fill and save PDF forms
  • Sign and share PDF documents
  • Password protect PDFs
  • Sync with cloud storage
  • Merge and organize PDFs
Features
Read full description

Ready to do more with PDFs on iPad & iPhone? Edit, read, sign and sync PDFs in the cloud with the powerful, lightweight Nitro PDF Pro app designed for iPad & iPhone users. Packed with features to help you stay productive on the go, Nitro PDF Pro for iPad & iPhone lets you edit, sign, share and manage your documents wherever you are - all in a secure and user-friendly interface. Get started for free with a 14-day trial today. “Superior PDF handling, & economical” “Nitro PDF Pro has become an essential tool in my daily business operations! It makes everything from document preparation to communication much easier for me.” “If you are looking for a workhorse app to handle your PDFs made by responsive developers, look no further...” -> With Nitro PDF Pro you can: EDIT PDFs ON THE GO * Easily edit PDF text wherever you are, on any iOS device * Make notes and add comments to PDFs for quick, on-the-go reference * Add images or mark-up PDFs with drawings, with stylus support for iPad ANNOTATE & HIGHLIGHT PDFs * Add annotations to PDF text and documents * Highlight text to stay organized and keep track of important information FILL & SAVE PDF FORMS * Fill and save PDF forms for fast & easy productivity * Keep your PDF forms secure with password protection SIGN & SHARE PDF DOCUMENTS * Sign & share PDF documents in a snap * Save text, signatures and images in your Library for easy re-use * Keep documents synced with the cloud for on-the-go signatures PROTECT, SECURE & SYNC PDFs * Password protect PDFs to keep your data and confidential information secure * Set the level of document encryption as required * Sync with the cloud to back up PDFs on iCloud, Dropbox, Google Drive, or Microsoft OneNote MERGE, EXPORT & ORGANIZE PDFs * Merge multiple documents into one PDF in just a few clicks for easy organization * Import, export & organize PDFs in folders for fast access and easy on-the-go editing * Duplicate, add, delete or rearrange pages for simple, custom document creation ADDITIONAL AMAZING PDF EDITOR FEATURES * Duplicate, add, delete, rotate and rearrange pages * Enable easier PDF reading with dark mode, search and zoom * Email & Airdrop your documents, with PDF flattening for maximum compatibility * View two documents simultaneously with multiple windows (iPadOS) * Bluetooth pressure-sensitive stylus support - automatically works with Apple Pencil * Support for Adonit Jot Touch and Jot Script styluses Still exploring PDF editors for iOS? No pressure! Give Nitro PDF Pro iOS a try for free with a 14-day trial and see how you like its features and functions. We think you’ll love the value we pack into our easy-to-use PDF iOS app. Questions and issues regarding our PDF app? We're here to help! Connect with Nitro through our Community Forum: https://community.gonitro.com/ NITRO POLICY https://www.gonitro.com/legal/privacy-policy https://www.gonitro.com/legal/terms-of-service

Screenshots

AI Viewer4 screens
Nitro PDF Pro4 screens

Verdict

The call

The clearest difference is rating: Nitro PDF Pro at 3.9 against AI Viewer's 2.9. Nitro PDF Pro also leads on ads (none vs shown) and ratings volume (161 vs 14). AI Viewer's advantage is update cadence (fortnightly vs every 2 months) and review sentiment (29% vs 13%). On price, in-app purchases, monetization model and device support there is nothing between them.

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

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. AI Viewer sells 1 in-app purchase, starting at $24.99 per year and Nitro PDF Pro sells 2 in-app purchases, starting at $19.99 per year. Whichever you choose, the download price is not the number that matters.

ReceptionRating · Positive reviews · Number of ratings

Nitro PDF Pro holds the better App Store score, 3.9 against 2.9. That said, the two scores are not equally well evidenced: Nitro PDF Pro has 161 ratings behind it against 14, so its average is the more settled of the two. Written reviews complicate that: 29% of AI Viewer's written reviews are positive against 13% of Nitro PDF Pro's, so the app with the better star average is not the one people write more warmly about.

UpkeepUpdate frequency

AI Viewer ships an update fortnightly, Nitro PDF Pro every 2 months. The most recent releases landed on September 21, 2026 and October 18, 2026 respectively.

Scorecard6 real differences · 4 level
AI Viewer versus Nitro PDF Pro: the parameters behind the verdict, then further details
ParameterAI ViewerNitro PDF Pro
PriceFreeFree
Rating2.9 (14 ratings)3.9 (161 ratings) — better
Positive reviews28.6% of reviews — better12.5% of reviews
Number of ratings14161 — better
Update frequencyFortnightly — betterEvery 2 months
AdsYesNo — better
In-app purchasesYesYes
MonetizationFree with in-app purchasesFree with in-app purchases
DevicesiPhone, iPad, iPod — betteriPhone, iPad
Requires iOS13.0 — better18.0
Further details — not scored
Size19 MB59 MB
Age rating4+4+
DeveloperVaibhav SinghalNitro Software, Inc.

Customer experience

AI Viewer

All ratings14 ratings
Positive42.9%
Neutral7.1%
Negative50.0%
Written reviews14 reviews
Positive28.6%
Neutral7.1%
Negative64.3%

Nitro PDF Pro

All ratings157 ratings
Positive70.1%
Neutral5.1%
Negative24.8%
Written reviews64 reviews
Positive12.5%
Neutral6.3%
Negative81.3%

Bugs and requests

AI Viewer

Not enough reviews yet to summarise bugs or requests.

Nitro PDF Pro

Reported bugs

19 issues
  • Cannot reorder PDF files
  • Crashes when opening PDFs from websites/email
  • Does not save markups or documents
  • Difficulty creating new folders
  • Cannot rotate pages
Show 14 more
  • Cannot markup/draw on PDFs with editing disabled
  • Does not save documents after editing
  • Cannot rotate PDFs
  • Program freezes up
  • Fails to save after deleting pages
  • App crashes after update
  • Editing is lost prior to crash
  • Crashes every time to edit a PDF
  • Cannot handle deleting pages
  • Crashes when opening fillable PDFs
  • Crashes when typing in fields
  • No Apple Pencil support
  • Stylus link gives 404 error
  • Bugs like suddenly not being able to draw

Requested features

10 requests
  • Keyboard support (Cmd + F for search)
  • Ability to cancel search with Esc
  • OCR and conversion to text documents on tablets
  • User manual for iPad app
  • Support for Apple Pencil
Show 5 more
  • Ability to create table of contents
  • Ability to create fillable forms
  • Ability to rearrange pages
  • Ability to add to library
  • More intuitive interface

In-app purchases

1 purchases

AI Viewer

Subscriptions1
  • Yearly Subscription$24.991 Year
2 purchases

Nitro PDF Pro

Subscriptions1
  • Annual Subscription14 Days trial$19.991 Year
One-time1
  • Nitro PDF Pro for iOS$9.99

Questions

Is AI Viewer free?
AI Viewer is free to download, with in-app purchases available.
Is Nitro PDF Pro free?
Nitro PDF Pro is free to download, with in-app purchases available.
Which has better reviews, AI Viewer or Nitro PDF Pro?
Nitro PDF Pro is rated higher. AI Viewer averages 2.9 out of 5 from 14 ratings, while Nitro PDF Pro averages 3.9 from 161 ratings.
Do AI Viewer or Nitro PDF Pro have ads?
AI Viewer shows ads; Nitro PDF Pro does not.
Which is updated more often, AI Viewer or Nitro PDF Pro?
AI Viewer ships an update fortnightly, and Nitro PDF Pro every 2 months. Most recently, AI Viewer was updated on September 21, 2026 and Nitro PDF Pro on October 18, 2026.

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