Comparison

PDF Protector vs OTC Memo

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

Head to head
About

PDF Protector

Secure your PDF documents with robust password protection and encryption. This tool allows you to restrict printing, copying, and content extraction, while also enabling decryption of protected files. Protect sensitive information quickly and reliably.

Highlights
  • Encrypt PDF files with password protection
  • Restrict printing and copying
  • Decrypt protected PDFs
  • Create reusable security profiles
  • Protect multiple files at once
  • Fast and intuitive interface
Features
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Protect your PDF documents with ease. PDF Protector is a simple and powerful tool for encrypting and decrypting PDF files. Secure your documents with industry-standard password protection to prevent unauthorized access. Set an open password and optionally restrict printing, copying, or content extraction to keep sensitive information safe. If you know the correct password, PDF Protector can also remove existing security settings and decrypt your PDF files. Features * Secure PDF files with industry-leading 256-bit AES encryption * Set an open password to secure your documents * Restrict printing, copying, and content extraction * Decrypt protected PDFs and remove password protection * Create reusable security profiles * Protect one or multiple PDF files at once * Fast, intuitive, and easy to use * Compatible with standard PDF readers Whether you’re protecting business documents, personal records, contracts, or confidential files, PDF Protector helps you secure your PDFs quickly and reliably.

About

OTC Memo

Features
Read full description

Ever find it a hassle to long-press, select, and copy when copying notes? This app splits sentences based on line breaks during editing, allowing you to copy each one with a one tap. Simply write your notes with line breaks, and they'll automatically organize like “tags.” Copy with a single tap, making it perfect for use as a “phrase dictionary” or “template text.” Copied tags change color for instant recognition. Full-text search supported. Supports creating QR codes for memos and scanning QR codes. Supports the memo sharing button.

Screenshots

PDF Protector4 screens
OTC Memo4 screens

Verdict

The call

The clearest difference is in-app purchases: OTC Memo at none against PDF Protector's 3. OTC Memo also leads on update cadence (weekly vs every 3 weeks) and iOS requirement (16.4 vs 18.0). 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 Protector sells 3 one-off in-app purchases. OTC Memo asks for nothing beyond the download.

UpkeepUpdate frequency

PDF Protector ships an update every 3 weeks, OTC Memo weekly. Both last shipped on October 17, 2026.

Scorecard3 real differences · 7 level
PDF Protector versus OTC Memo: the parameters behind the verdict, then further details
ParameterPDF ProtectorOTC Memo
PriceFreeFree
Rating5.0 (4 ratings) — better—
Positive reviews71.1% of reviews—
Number of ratings4 — better—
Update frequencyEvery 3 weeksWeekly — better
AdsNoNo
In-app purchasesYesNo — better
MonetizationFree—
DevicesiPhone, iPad, MaciPhone, iPad, iPod
Requires iOS18.016.4 — better
Further details — not scored
Size9 MB41 MB
Age rating4+4+
DeveloperDaniel WittKatsushi Kawamori

In-app purchases

3 purchases

PDF Protector

One-time3
  • Full Version for iPhone & iPad$4.99
  • Full Version for Mac$9.99
  • Full Version for All Devices$12.99
None

OTC Memo

No in-app purchases

Questions

Is PDF Protector free?
PDF Protector is free to download, with in-app purchases available.
Is OTC Memo free?
OTC Memo is free to download, with no in-app purchases.
Do PDF Protector or OTC Memo have ads?
Neither PDF Protector nor OTC Memo shows ads.
Which is updated more often, PDF Protector or OTC Memo?
PDF Protector ships an update every 3 weeks, and OTC Memo weekly. Most recently, PDF Protector was updated on October 17, 2026 and OTC Memo on October 17, 2026.

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