Comparison

PlainPDF vs PDF Studio

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

Head to head
About

PlainPDF

Features
Read full description

Scan, fill in, sign, annotate and compress PDFs. Every tool is free, with no watermarks, no account and no subscription. Your files are processed on your device and never uploaded. SCAN • Scan documents with automatic edge detection • Crisp black & white mode for text, plus colour and greyscale • ID cards: put the front and back on one page at real card size • Get a file name suggested from the page, like "Electricity Bill Oct 2026" • Make scans searchable with on-device text recognition FILL, SIGN & ANNOTATE • Fill in PDF forms: type straight into the fields, or fill them in one tap from My details • Sign PDFs: draw or type your signature, add the date, text and ticks • Highlight, underline and strike out text, draw with a pen or marker, and add notes • Organize pages: reorder, rotate, delete, duplicate, insert and extract • Add watermarks like CONFIDENTIAL or COPY, and page numbers CONVERT • Merge PDFs and photos into one file • Split PDFs by page, by range or every few pages • Compress PDFs for email and upload limits, or set a target size like "under 2 MB" • Turn photos into PDFs with A4, Letter or fit-to-photo pages • Copy text from any scan or photo PDF • Extract images from PDFs, or save pages as images PRIVACY & SECURITY • Redact: find emails, phone numbers, card, bank and ID numbers, and black them out for good before you share • Add a password to a PDF, or remove a password you know QR CODES THAT NEVER EXPIRE • Create QR codes for links, Wi-Fi, contacts, email, phone, SMS, UPI payments and locations • The information is stored in the code itself, so it keeps working without any server • Every code is tested before you save it • Scan QR codes and see where a link really goes before opening it WORKS THE WAY YOU DO • Files app and "Open in PlainPDF" from Mail, Messages and other apps • Designed for iPhone and iPad, in light and dark mode • In English, Spanish, Portuguese, German, French, Italian and Japanese FREE, HONESTLY Every tool is free with ads. PlainPDF Pro is a one-time purchase that removes ads, adds batch processing for many files at once, and unlimited text recognition on large documents. No subscription, ever. No account. Your files never leave your device. Questions or ideas: hello@smileappsstudio.com

About

PDF Studio

Features
Read full description

PDF Studio is your private, all-in-one PDF toolkit — over 70 tools that run entirely on your device. No account, no tracking, no uploads. SCAN & CREATE • Scan documents with automatic edge detection • Turn photos or typed text into clean PDFs EDIT & ORGANIZE • Merge, split, reorder, rotate and delete pages • Compress to shrink file size — even to a target limit • Crop, resize, add margins and page numbers CONVERT • PDF to Word, plain text or images • Make scanned pages searchable with on-device OCR SIGN & PROTECT • Fill forms and sign documents by hand • Password-protect, remove passwords and redact sensitive info • Add watermarks, stamps and headers Beautiful on iPhone, iPad and Mac, with iCloud sync to keep your library on every device. Find any tool instantly with search, favorites and recents. PDF Studio Pro unlocks every tool with a single purchase or subscription. Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

Screenshots

PlainPDF4 screens
PDF Studio4 screens

Verdict

The call

The clearest difference is ads: PDF Studio at none against PlainPDF's shown. PDF Studio also leads on update cadence (every 9 days vs every 2 months). On price, in-app purchases, device support and iOS requirement there is nothing between them.

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

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

Both are free to download. PlainPDF sells 1 one-off in-app purchase and PDF Studio sells 2 in-app purchases, starting at $9.99 per year. Whichever you choose, the download price is not the number that matters.

UpkeepUpdate frequency

PlainPDF ships an update every 2 months, PDF Studio every 9 days. The most recent releases landed on November 10, 2026 and November 5, 2026 respectively.

Scorecard2 real differences Ā· 4 level
PlainPDF versus PDF Studio: the parameters behind the verdict, then further details
ParameterPlainPDFPDF Studio
PriceFreeFree
Update frequencyEvery 2 monthsEvery 9 days — better
AdsYesNo — better
In-app purchasesYesYes
DevicesiPhone, iPadiPhone, iPad, Mac — better
Requires iOS17.017.0
Further details — not scored
Size9 MB18 MB
Age rating4+4+
DeveloperSwaminathan LBirkan Aksoy

In-app purchases

1 purchases

PlainPDF

One-time1
  • PlainPDF Pro$4.99
2 purchases

PDF Studio

Subscriptions1
  • PDF Studio Pro$9.991 Year
One-time1
  • PDF Studio Pro (Lifetime)$24.99

Questions

Is PlainPDF free?
PlainPDF is free to download, with in-app purchases available.
Is PDF Studio free?
PDF Studio is free to download, with in-app purchases available.
Do PlainPDF or PDF Studio have ads?
PlainPDF shows ads; PDF Studio does not.
Which is updated more often, PlainPDF or PDF Studio?
PlainPDF ships an update every 2 months, and PDF Studio every 9 days. Most recently, PlainPDF was updated on November 10, 2026 and PDF Studio on November 5, 2026.

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