Comparison

PDF Slim vs UnderLimit

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

Head to head
About

PDF Slim

Reduce the size of your PDF files with adjustable quality settings. Save or share compressed documents directly from the application. Access detailed information about each PDF.

Highlights
  • Compress PDF files
  • Adjustable quality levels
  • Save compressed PDFs
  • Share instantly
  • View PDF details
Features
Read full description

A smart compression app that quickly and easily reduces PDF file size! • Every Feature, No Payment Use every feature right away — no payment required. • Your Choice of Compression Quality Choose from three quality levels — Low, Medium, and High — to control how much your PDFs are compressed. The lower the quality, the smaller the file. • Detailed PDF Information Check key details at a glance, including file name, page count, file size, and creation date. • Separate Save & Instant Sharing Your original PDF stays untouched — the compressed copy is saved separately and can be shared instantly from the app.

About

UnderLimit

Features
Read full description

Make your files fit the limit. UnderLimit helps you reduce photos and PDFs to the file size you actually need. Choose your target size, and UnderLimit handles the compression while preserving the best quality possible. PERFECT FOR FILE SIZE LIMITS Need a photo under 1 MB? A PDF under 5 MB? An attachment small enough to upload or send? Set the target size and let UnderLimit do the work. PHOTO COMPRESSION • Compress photos to a target file size • Reduce image size in KB or MB • Keep the best quality possible • Quickly prepare images for uploads, forms, email, and sharing PDF COMPRESSION • Reduce PDF file size • Choose the maximum size you need • Prepare PDFs for upload limits and attachments • Simple, fast workflow SMART RECOMMENDATIONS Not sure which target size to choose? UnderLimit can help you select an appropriate size for your file. PRIVATE BY DESIGN Your files are processed directly on your device. Your photos and PDFs don't need to be uploaded to a remote server for compression. SIMPLE PRICING Start using UnderLimit for free. If you need more, unlock UnderLimit Unlimited with a one-time purchase. No subscription. No ads. No account required. UNDERLIMIT IS USEFUL FOR • Online forms and portals • Email attachments • Applications and document submissions • Websites with maximum upload sizes • Reducing photos before sharing • Compressing PDFs for size-restricted uploads Stop guessing compression levels. Choose the size you need and make your file fit the limit.

Screenshots

PDF Slim3 screens
UnderLimit4 screens

Verdict

The call

The clearest difference is in-app purchases: PDF Slim at none against UnderLimit's 1. PDF Slim also leads on iOS requirement (15.0 vs 17.0). UnderLimit's advantage is update cadence (every 2 days vs weekly). 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. UnderLimit sells 1 one-off in-app purchase. PDF Slim asks for nothing beyond the download.

UpkeepUpdate frequency

PDF Slim ships an update weekly, UnderLimit every 2 days. The most recent releases landed on October 10, 2026 and October 14, 2026 respectively.

Scorecard3 real differences · 6 level
PDF Slim versus UnderLimit: the parameters behind the verdict, then further details
ParameterPDF SlimUnderLimit
PriceFreeFree
Rating5.0 (1 ratings) — better—
Number of ratings1 — better—
Update frequencyWeeklyEvery 2 days — better
AdsNoNo
In-app purchasesNo — betterYes
MonetizationAd-supported—
DevicesiPhone, iPad, iPod — betteriPhone, iPad
Requires iOS15.0 — better17.0
Further details — not scored
Size4 MB4 MB
Age rating4+4+
DeveloperMBG StudioALESSANDRO VINCENZO DEL BALZO

In-app purchases

None

PDF Slim

No in-app purchases

1 purchases

UnderLimit

One-time1
  • UnderLimit Unlimited$2.99

Questions

Is PDF Slim free?
PDF Slim is free to download, with no in-app purchases.
Is UnderLimit free?
UnderLimit is free to download, with in-app purchases available.
Do PDF Slim or UnderLimit have ads?
Neither PDF Slim nor UnderLimit shows ads.
Which is updated more often, PDF Slim or UnderLimit?
PDF Slim ships an update weekly, and UnderLimit every 2 days. Most recently, PDF Slim was updated on October 10, 2026 and UnderLimit on October 14, 2026.

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