Comparison

HLL Pdf Reader vs String Theory!

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

Head to head
About

HLL Pdf Reader

This app offers a streamlined PDF reading experience with an iBooks-inspired interface. It provides features like recent reading history, page cropping for larger content views, and an outline for easy navigation. Zooming is simplified with double-tap gestures.

Highlights
  • iBooks-like design
  • Reading history
  • Page cropping
  • Document outline
  • Double-tap zoom
  • Automatic fit on rotation
Features
Read full description

Universal app - Support for iPhone / iPad iBooks-like design - Support your reading experience with simple User Interface. Recently read books - Show your reading histories. Therefore you can find books that you read recently. Cropping - Crop page merging to show contents bigger automatically. Outline - Show current document structure so that you can see your position and move around easily. No more pinch in/out. - Zoom in/out with double tap. - Fit document to device size automatically when rotating.

About

String Theory!

Features
Read full description

String Theory is a visual detective board app that helps you organize ideas, clues, and connections in one place. Create interactive boards where you can add Polaroid-style photos, notes, tags, and images, pin them freely, and connect everything with strings to reveal patterns and relationships. Perfect for detectives, writers, students, researchers, and creative thinkers, String Theory turns complex information into a clear visual map. Whether you’re solving a mystery, planning a story, organizing research, or brainstorming ideas, your board evolves as your thoughts connect. Features: - Create unlimited detective boards - Add Polaroid photos, images, and notes - Pin items anywhere on the board - Connect clues using realistic strings - Use tags to organize and group ideas - Clean, intuitive, and distraction-free design Organize your thoughts visually. See the connections. Follow the strings. Apple Terms of Use (EULA) https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

Screenshots

HLL Pdf Reader1 screens
String Theory!3 screens

Verdict

The call

The clearest difference is in-app purchases: HLL Pdf Reader at none against String Theory!'s 3. HLL Pdf Reader also leads on ads (none vs shown). On price, 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

Both are free to download. String Theory! sells 3 in-app purchases, starting at $2.99 per 7 days. HLL Pdf Reader asks for nothing beyond the download.

Scorecard2 real differences · 7 level
HLL Pdf Reader versus String Theory!: the parameters behind the verdict, then further details
ParameterHLL Pdf ReaderString Theory!
PriceFreeFree
Rating5.0 (1 ratings) — better—
Number of ratings1 — better—
Update frequencyEvery 9 months—
AdsNo — betterYes
In-app purchasesNo — betterYes
MonetizationFree—
DevicesiPhone, iPad, iPodiPhone, iPad, iPod
Requires iOS15.0 — better15.1
Further details — not scored
Size15 MB56 MB
Age rating4+4+
Developerhades lade lamSynthify Inc

In-app purchases

None

HLL Pdf Reader

No in-app purchases

3 purchases

String Theory!

Subscriptions2
  • Weekly$2.997 Days
  • Yearly$24.991 Year
One-time1
  • One Time$29.99

Questions

Is HLL Pdf Reader free?
HLL Pdf Reader is free to download, with no in-app purchases.
Is String Theory! free?
String Theory! is free to download, with in-app purchases available.
Do HLL Pdf Reader or String Theory! have ads?
String Theory! shows ads; HLL Pdf Reader does not.

Other comparisons