Comparison

USB Disk Pro vs Strongbox Zero

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

Head to head
About

USB Disk Pro

Manage and view documents on your iPhone and iPad with this powerful file manager. It offers a built-in viewer, easy file transfers via iTunes or Wi-Fi, and supports numerous cloud services. Secure your files with encryption and access them from various locations.

Highlights
  • Store and view files
  • Built-in document viewer
  • iTunes and Wi-Fi file transfers
  • Cloud service integration
  • File encryption and protection
  • Supports Files app
Features
Read full description

USB Disk Pro lets you store, view and manage documents on your iPhone and iPad. It has an amazing built in document viewer and is very easy to use, with a simple and intuitive interface, yet it contains many powerful features. Drag and drop files in iTunes to transfer them to your iPhone / iPad, then view them anywhere! TUAW - "USB Disk is [...] a nicely designed one." Lifehacker - "The Best. USB Disk for iOS gives you a fast and easy way to transfer documents and images to your device." Apple - "New and Noteworthy" TOP REASONS TO BUY • Store and view files. • Open multiple documents in different pages. • Restores last viewing position. • Navigate using swipes (like Photos / iBooks app). • Thumbnails let you preview your files. • Protect & encrypt files using Apple's Data Protection. • Supports the Files application (file provider for iOS 11+). MORE FEATURES • View and download email attachments. • Full screen file viewer. • Copy, paste, cut, delete and create files. • USB file transfers. • File transfers without iTunes over WiFi. • TV / VGA out. • Slideshow with adjustable delay. • Fast scrolling, page up/down functionalities. • Email your documents. • Lock code. • Download web files. • In app web browser. • Storage provider for other apps. • Background audio. BROWSING LOCATIONS • Local files. • Dropbox. • Google Drive. • OneDrive, SharePoint. • Box. • Evernote. • WebDAV and WWW servers. • FTP, SFTP servers. • Device's Photo Library. READING FILE TYPES • PDF files. • Compressed files (zip, rar). • MS Office documents. • iWork documents. • Pictures (jpg, png, gif, ...). • eBooks (pdf, ePub, html, txt, ...). • Comics (cbr, cbz, pdf, ...). • Audio files (mp3, m4a, wav, ...). • Video files (m4v, mov, avi, mkv, ...). EDITING FILE TYPES • ZIP files. • Small txt files. • PDF annotations. UPDATES Buy now and get free updates.

About

Strongbox Zero

This app securely stores and protects your passwords with a master password. It supports open-source formats and offers advanced security features like biometric unlock and hardware token protection. It's designed for users who prefer a local-only password management solution.

Highlights
  • Local-only password storage
  • Biometric and PIN unlock
  • YubiKey hardware token protection
  • Military-grade cryptography
  • Password auditing for weak passwords
  • Secure document attachment viewer
  • Import/Export via Files app and Email
Features
Read full description

Strongbox Zero is a version of the well known and loved Strongbox with all of the networking code and as many third party libraries stripped out as we could! Think of it as the Drag Racer version of Strongbox! If you're a fan of Local Only password managers this could be the right choice for you. We recommend you get to know (and love!) the regular Strongbox first through the Freemium app. Once you're happy and sure you want to go local only, go for Strongbox Zero... Strongbox Zero is an application for keeping all your passwords safely stored and protected by one master password. Supporting the open source Password Safe and KeePass formats. *** Features *** - Face ID/Touch ID Unlock for the ultimate in convenience, security and speed. - PIN Code Unlock with a Duress PIN option for those tricky situations. - YubiKey protection - secure your databases with a hardware token. - Secure - protected by time tested military grade cryptography. - Private - Isolated In-App attachments viewer for your sensitive documents, photos & videos. - Audit your passwords - Automatically check your database for weak passwords - Search your entire set of passwords and secrets instantly and powerfully, with deep search. Autocomplete new entries, and auto generate secure passwords. - Compatible - Import/Export by Files app, Email, CSV, iTunes File Sharing - Standards compliant - using the time tested Password Safe and KeePass formats so you can import any existing password safe you have. - Features galore - Incredibly configurable password generation including Diceware (XKCD) & regular passwords. - Timed Auto Clear Clipboard. - Entry History. - KeePass Field References, Tags & Custom Icons. - Two Factor Authentication codes (TOTP) - QR Code, Steam & Manual. --------------------------------------------------------------------- • Payment will be charged to iTunes Account at confirmation of purchase • Strongbox Privacy Policy may be found here: https://strongboxsafe.com/privacy-policy/ • Strongbox Terms of Use may be found here: https://strongboxsafe.com/terms/

Screenshots

USB Disk Pro4 screens
Strongbox Zero4 screens

Verdict

The call

The clearest difference is update cadence: Strongbox Zero at every 2 weeks against USB Disk Pro's every 3 months. Strongbox Zero also leads on review sentiment (75% vs 66%). USB Disk Pro's advantage is rating (4.5 vs 4.3) and ratings volume (142 vs 21). On price, ads, in-app purchases and monetization model 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

USB Disk Pro costs $99.99 and Strongbox Zero $99.99 up front. Neither carries in-app purchases, so what you see is what you pay.

ReceptionRating · Positive reviews · Number of ratings

USB Disk Pro holds the better App Store score, 4.5 against 4.3. That said, the two scores are not equally well evidenced: USB Disk Pro has 142 ratings behind it against 21, so its average is the more settled of the two. Written reviews complicate that: 66% of USB Disk Pro's written reviews are positive against 75% of Strongbox Zero's, so the app with the better star average is not the one people write more warmly about.

UpkeepUpdate frequency

USB Disk Pro ships an update every 3 months, Strongbox Zero every 2 weeks. The most recent releases landed on October 22, 2026 and October 19, 2026 respectively.

Scorecard4 real differences · 6 level
USB Disk Pro versus Strongbox Zero: the parameters behind the verdict, then further details
ParameterUSB Disk ProStrongbox Zero
Price$99.99$99.99
Rating4.5 (142 ratings) — better4.3 (21 ratings)
Positive reviews65.6% of reviews75.0% of reviews — better
Number of ratings142 — better21
Update frequencyEvery 3 monthsEvery 2 weeks — better
AdsNoNo
In-app purchasesNoNo
MonetizationPaidPaid
DevicesiPhone, iPad, Apple TV, Apple WatchiPhone, iPad, iPod, Mac, Apple Watch — better
Requires iOS16.015.0 — better
Further details — not scored
Size215 MB96 MB
Age rating17+4+
DeveloperImesart S.a.r.l.Phoebe Code Limited

Customer experience

USB Disk Pro

All ratings142 ratings
Positive89.4%
Neutral4.2%
Negative6.3%
Written reviews607 reviews
Positive65.6%
Neutral11.9%
Negative22.6%

Strongbox Zero

All ratings21 ratings
Positive85.7%
Neutral0.0%
Negative14.3%
Written reviews20 reviews
Positive75.0%
Neutral0.0%
Negative25.0%

Bugs and requests

USB Disk Pro

Reported bugs

3 issues
  • App closing unexpectedly when using certain features
  • Inability to open large files without crashing
  • Inconsistent file handling and naming

Requested features

4 requests
  • Advanced video player controls (fast forward, slow motion, zoom)
  • Basic image editing tools
  • Improved file/folder organization and naming
  • Integration with more cloud storage services

Strongbox Zero

Not enough reviews yet to summarise bugs or requests.

In-app purchases

None

USB Disk Pro

No in-app purchases

None

Strongbox Zero

No in-app purchases

Questions

Is USB Disk Pro free?
USB Disk Pro costs $99.99, with no in-app purchases.
Is Strongbox Zero free?
Strongbox Zero costs $99.99, with no in-app purchases.
Which has better reviews, USB Disk Pro or Strongbox Zero?
USB Disk Pro is rated higher. USB Disk Pro averages 4.5 out of 5 from 142 ratings, while Strongbox Zero averages 4.3 from 21 ratings.
Do USB Disk Pro or Strongbox Zero have ads?
Neither USB Disk Pro nor Strongbox Zero shows ads.
Which is updated more often, USB Disk Pro or Strongbox Zero?
USB Disk Pro ships an update every 3 months, and Strongbox Zero every 2 weeks. Most recently, USB Disk Pro was updated on October 22, 2026 and Strongbox Zero on October 19, 2026.

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