Comparison

PDF Studio vs Sign Docs

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

Head to head
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/

About

Sign Docs

Read full description

Fill and sign any document in a minute – right from your iPhone. Scan paper with the camera, type into the fields, sign with your finger (or let AI make a signature from your name) and send the PDF anywhere. No printer, no scanner, no account. SCAN TO PDF • Point the camera at any paper: the page is found, cropped and straightened automatically • Multi-page scans, photos from your library, screenshots • Clean, sharp PDFs ready to fill and sign FILL IN ANY FORM • Type into the fields of interactive PDFs • Add text, dates and checkmarks anywhere on scanned forms • Save a form as a template and reuse it in seconds SIGN YOUR WAY • Draw your signature with a finger • Photograph your real signature from paper – the background is removed automatically • Let AI create a signature from your name or refine your drawing • Add stamps: APPROVED, PAID, URGENT, COPY or your own text, or scan a real stamp KNOW WHAT YOU'RE SIGNING • AI Check reads the document and explains it in plain words • Key terms, hidden fees and risky clauses are flagged before you sign • Works with contracts, leases, agreements and forms OPEN FROM ANYWHERE • Files, Photos, Google Drive and Dropbox • Word documents (.docx, .doc) are converted to PDF • Password-protected PDFs open too, and big scans can be compressed SEND, PRINT, SAVE • Share the signed PDF by mail or messenger, print it or save it to Files • The original stays editable; your signature is flattened into the copy you send FREE AND PRO Scanning, filling and signing are free without limits. Sign Docs Pro unlocks exporting, printing and saving your documents, plus unlimited AI Check and AI signatures. Pro is available as a monthly or a yearly subscription. Need just one document? Unlock it with a one-time purchase, then fix it and export it again whenever you like. Prices are shown in the app before you buy. Payment is charged to your Apple ID account at confirmation of purchase. The subscription renews automatically unless it is cancelled at least 24 hours before the end of the current period, and your account is charged for renewal within 24 hours before the end of the period. You can manage and cancel subscriptions in your App Store account settings. Privacy Policy: https://signdocs.paralegalmind.com/privacy Terms of Use: https://signdocs.paralegalmind.com/terms Questions or ideas? Open Settings → Contact us in the app. Available in English, Spanish, German, French, Italian, Portuguese (Brazil) and Russian.

Screenshots

PDF Studio4 screens
Sign Docs4 screens

Verdict

The call

The clearest difference is device support: PDF Studio at 3 against Sign Docs's 1. On price, update cadence, ads and in-app purchases 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. PDF Studio sells 2 in-app purchases, starting at $9.99 per year and Sign Docs sells 4 in-app purchases, starting at $5.99 per 7 days. Whichever you choose, the download price is not the number that matters.

UpkeepUpdate frequency

PDF Studio ships an update every 9 days, Sign Docs every 3 weeks. The most recent releases landed on November 5, 2026 and November 6, 2026 respectively.

Scorecard1 real difference Ā· 5 level
PDF Studio versus Sign Docs: the parameters behind the verdict, then further details
ParameterPDF StudioSign Docs
PriceFreeFree
Update frequencyEvery 9 days — betterEvery 3 weeks
AdsNoNo
In-app purchasesYesYes
DevicesiPhone, iPad, Mac — betteriPhone
Requires iOS17.017.0
Further details — not scored
Size18 MB16 MB
Age rating4+4+
DeveloperBirkan AksoyAndrei Alferchyk

In-app purchases

2 purchases

PDF Studio

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

Sign Docs

Subscriptions3
  • Pro Weekly3 Days trial$5.997 Days
  • Pro Monthly$12.991 Month
  • Pro Yearly$49.991 Year
One-time1
  • One Document$1.99

Questions

Is PDF Studio free?
PDF Studio is free to download, with in-app purchases available.
Is Sign Docs free?
Sign Docs is free to download, with in-app purchases available.
Do PDF Studio or Sign Docs have ads?
Neither PDF Studio nor Sign Docs shows ads.
Which is updated more often, PDF Studio or Sign Docs?
PDF Studio ships an update every 9 days, and Sign Docs every 3 weeks. Most recently, PDF Studio was updated on November 5, 2026 and Sign Docs on November 6, 2026.

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