Comparison

U vs PDF Diet

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

Head to head
About

U

This application provides secure, two-shake access to areas protected by U-Prox access controllers. It can store multiple keys, allowing for use in various independent locations with an easy-to-use interface.

Highlights
  • Two-shake access
  • Stores multiple keys
  • Independent facility use
  • U-Prox brand style interface
  • Easy usability
Features
Read full description

U-Prox Mobile ID is used to get two-shake access to the area secured by U-Prox family access controllers. The application stores more than one key - it makes possible to use U-Prox Mobile ID in independent facilities. U-Prox brand style interface makes the application usability as easy as it possible.

About

PDF Diet

Read full description

Shrink a PDF before you email it or upload it from your iPhone or iPad. Open a scanned form, a report with photos, or another large PDF from Files. PDF Diet compresses it right on your device, so you can work offline. Find the right file size Choose Light, Medium, High, or Strong. Check the file size for each preset and compare the original and compressed pages in a synchronized preview. See what changed before you share. Keep documents readable PDF Diet checks what’s inside the document. On supported PDFs, it can recompress embedded images while keeping text and vector graphics sharp. Results depend on what’s in the file. Clean up a copy Delete unwanted pages or choose which details to remove, including author metadata, comments, bookmarks, attachments, and links. Save to Files or share Export a separate copy and keep your original intact. Save the result to Files or send it through the share sheet with Mail, Messages, or AirDrop.

Screenshots

U3 screens
PDF Diet4 screens

Verdict

The call

The clearest difference is price: U at Free against PDF Diet's $1.99. PDF Diet's advantage is update cadence (every 10 days vs every 2 months). On ads, in-app purchases, device support and iOS requirement 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

U is free to download; PDF Diet costs $1.99 up front. Neither carries in-app purchases, so what you see is what you pay.

UpkeepUpdate frequency

U ships an update every 2 months, PDF Diet every 10 days. The most recent releases landed on November 11, 2026 and November 10, 2026 respectively.

Scorecard2 real differences · 8 level
U versus PDF Diet: the parameters behind the verdict, then further details
ParameterUPDF Diet
PriceFree — better$1.99
Rating4.8 (27 ratings) — better—
Positive reviews18.2% of reviews—
Number of ratings27 — better—
Update frequencyEvery 2 monthsEvery 10 days — better
AdsNoNo
In-app purchasesNoNo
MonetizationFree—
DevicesiPhone, iPad, Apple Watch — betteriPhone, iPad
Requires iOS16.0 — better17.1
Further details — not scored
Size85 MB3 MB
Age rating4+4+
Developera2softinArtem Svitelskyi

In-app purchases

None

U

No in-app purchases

None

PDF Diet

No in-app purchases

Questions

Is U free?
U is free to download, with no in-app purchases.
Is PDF Diet free?
PDF Diet costs $1.99, with no in-app purchases.
Do U or PDF Diet have ads?
Neither U nor PDF Diet shows ads.
Which is updated more often, U or PDF Diet?
U ships an update every 2 months, and PDF Diet every 10 days. Most recently, U was updated on November 11, 2026 and PDF Diet on November 10, 2026.

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