Comparison

PDF Secure vs PDF Lock

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

Head to head
About

PDF Secure

Secure your PDF documents by adding password protection, ensuring they cannot be opened without authorization. You can also easily remove existing password protection from your files. This app offers a straightforward process for safeguarding your sensitive information.

Highlights
  • Password protect PDF documents
  • Remove PDF password protection
  • Cross-platform compatibility
  • Export to various locations
  • Dark mode support
Read full description

Protect your PDF documents with a password. The PDF won't open without the password. It works on any platform. PDF Secure also allows you to completely remove the password protection of a document. Using PDF Secure is very simple: • Select a PDF document from your files • Choose a password (ideally strong) and do not forget it • Export anywhere (Files app, any cloud drive, E-mail, AirDrop, Messages, ...) → The password will now be requested at any attempt to open the PDF (on all platforms) PDF Secure is compatible with the dark mode. And it's 100% free (no in-app purchases, no ads). NO DATA COLLECTION. Everything happens on device. Your privacy matters. Enjoy!

About

PDF Lock

Features
Read full description

Forgot the password on an important PDF? Need to secure a document before sharing? PDF Lock: Unlock & Protect makes it simple — unlock or password-protect any PDF right on your iPhone or iPad, in just a few taps. Your files never leave your device. Everything is processed locally using Apple's built-in PDF engine. No uploads. No cloud. No account required. No ads. Just fast, private PDF security whenever you need it. UNLOCK PDFs IN SECONDS
Remove password protection from any PDF and get back to reading, editing, or sharing. Enter the current password, and your unlocked file is ready to export — to Files, Mail, WhatsApp, or any app you use. LOCK PDFs WITH A PASSWORD
Keep sensitive documents safe before you send them. Add strong password protection to any PDF so only the right people can open it. (PDF Lock is included with PDF Lock: Unlock & Protect Pro.) BUILT-IN PDF VIEWER
Preview your unlocked or locked PDF inside the app before you export. Scroll through every page with a clean, full-screen viewer — no extra apps needed. EASY EXPORT & SHARE
Save processed PDFs to the Files app or share them instantly with the native iOS share sheet. Your workflow stays simple and familiar. PDF HISTORY
Revisit your recently processed files without hunting through folders. Open past PDFs directly from your history list and pick up where you left off. HOW IT WORKS 1. Select a PDF from Files, Mail, or any app 2. Unlock it (enter the password) or lock it (set a new one) 3. Preview, export, or share — done PRIVACY YOU CAN TRUST * 100% on-device processing — files are never sent to a server * No account or sign-up required * No ads, ever * Your passwords and documents stay on your device FREE TO START
Get 2 free PDF unlocks every day — no credit card, no commitment. Perfect for occasional use. UPGRADE TO PRO
Go unlimited with PDF Lock: Unlock & Protect Pro: * Unlimited PDF unlocks — no daily limits * Lock PDFs with password protection * Extended PDF history (last 20 files) * Priority support Download PDF Lock: Unlock & Protect today and take control of your PDF security — privately, quickly, and right from your pocket. Subscription automatically renews unless cancelled at least 24 hours before the end of the current period. Manage or cancel anytime in your App Store account settings. Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

Screenshots

PDF Secure4 screens
PDF Lock4 screens

Verdict

The call

The clearest difference is in-app purchases: PDF Secure at none against PDF Lock's 2. PDF Secure also leads on iOS requirement (13.0 vs 17.6). PDF Lock's advantage is update cadence (fortnightly vs every 9 months). On price, ads 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. PDF Lock sells 2 in-app purchases, starting at $0.99 per month. PDF Secure asks for nothing beyond the download.

UpkeepUpdate frequency

PDF Secure ships an update every 9 months, PDF Lock fortnightly. Both last shipped on October 25, 2026.

Scorecard3 real differences · 7 level
PDF Secure versus PDF Lock: the parameters behind the verdict, then further details
ParameterPDF SecurePDF Lock
PriceFreeFree
Rating4.8 (383 ratings) — better—
Positive reviews98.8% of reviews—
Number of ratings383 — better—
Update frequencyEvery 9 monthsFortnightly — better
AdsNoNo
In-app purchasesNo — betterYes
MonetizationFree—
DevicesiPhone, iPad, iPod — betteriPhone, iPad
Requires iOS13.0 — better17.6
Further details — not scored
Size1 MB17 MB
Age rating4+4+
DeveloperiSolid appsNikunj Gondaliya

In-app purchases

None

PDF Secure

No in-app purchases

2 purchases

PDF Lock

Subscriptions2
  • Monthly - PDF Lock & Unlock Pro$0.991 Month
  • Yearly - PDF Lock & Unlock Pro$7.991 Year

Questions

Is PDF Secure free?
PDF Secure is free to download, with no in-app purchases.
Is PDF Lock free?
PDF Lock is free to download, with in-app purchases available.
Do PDF Secure or PDF Lock have ads?
Neither PDF Secure nor PDF Lock shows ads.
Which is updated more often, PDF Secure or PDF Lock?
PDF Secure ships an update every 9 months, and PDF Lock fortnightly. Most recently, PDF Secure was updated on October 25, 2026 and PDF Lock on October 25, 2026.

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