Comparison

TOPLAPapp vs Audulus 4

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

Head to head
About

TOPLAPapp

This app offers a unique sonic puzzle experience using a virtual machine for sound synthesis. Users control the machine by placing command letters and adjusting parameter sliders to generate experimental, often noisy, electronic music.

Highlights
  • Virtual machine for sound synthesis
  • Instruction-based sound generation
  • Parameter sliders for sound control
  • Grid-based command placement
  • Experimental sonic art focus
  • Live coding principles
Features
Read full description

TOPLAPapp is a sonic puzzle based around a virtual machine for sound synthesis. This machine accepts a few valid instructions represented by the letters T, O, P, L, A, and p, and you control it by placing each command letter within a grid, along with setting some associated parameter sliders. The machine rushes through the instruction set to create output sounds, which are usually of a somewhat noisy character, hopefully interestingly so. The historical antecedents include instruction synthesis as pioneered at the Institute of Sonology in the 1970s, and the live coding movement, of modifying a running program as it acts. This app is intended for those interested in more experimental sonic art: don't download unless you are open to stranger computer music sounds ((http://www.toplap.org).

About

Audulus 4

Create and shape sounds with a professional-grade modular synthesizer environment. Explore a vast library of modules for synthesis and sound design, with the option to expand your toolkit with premium instruments and effects. Available across Apple devices for seamless workflow.

Highlights
  • Modular synthesizer environment
  • Sound design tools
  • Real-time audio shaping
  • Extensive module library
  • Premium Pro Modules (in-app purchases)
  • Cross-device iCloud sync
  • AUv3 plugin support
Features
Read full description

Build synthesizers. Design sounds. Shape audio in real time. All with professional-grade, low-latency performance ready for live use — and it’s free. Audulus gives you a complete modular environment at no cost. Its clean, fluid interface stays out of the way so you can focus on what matters: exploring sound. A modular playground with room to grow — from first experiments to advanced designs. Looking for more? Discover the Pro Module series: premium instruments and effects that show what’s possible when world-class sound design meets true modular freedom. Each Pro Module is crafted specifically for Audulus, giving you new ways to expand your sonic toolkit. Available on iPhone, iPad, and Mac — your modular system travels with you. ▶ What People Are Saying: "gem for Apple platforms – gorgeous, fluid" — Peter Kirn, createdigitalmusic.com "stunning!" — Richard Devine, devinesound.net "Remarkable gesture control" — sequencer.de ▶ Join our forum and Discord community! ▶ What You Get: • Complete modular environment — free to download and explore • Pro Module series — premium modules available as in-app purchases • Available on iPhone, iPad, and Mac with iCloud sync • Standalone app or AUv3 plugin • Deep node library for building from scratch • Extensive module library for synthesis and sound design • Multi-channel signal flow for polyphony and complex routing • Next-gen multi-core audio processing • Smooth, high-performance graphics even with massive patches • MIDI I/O with MIDI learn • GLSL shader node for creating advanced visuals • Lua scripting for custom DSP and vector graphics Terms of Use: https://audulus.com/terms.html

Screenshots

TOPLAPapp2 screens
Audulus 44 screens

Verdict

The call

The clearest difference is rating: TOPLAPapp at 4.8 against Audulus 4's 4.3. TOPLAPapp also leads on in-app purchases (none vs 27) and review sentiment (95% vs 69%). Audulus 4's advantage is update cadence (monthly vs every 49 months) and ratings volume (74 vs 4). 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. Audulus 4 sells 27 in-app purchases, starting at $4.99 per month. TOPLAPapp asks for nothing beyond the download.

ReceptionRating · Positive reviews · Number of ratings

TOPLAPapp holds the better App Store score, 4.8 against 4.3. That said, the two scores are not equally well evidenced: Audulus 4 has 74 ratings behind it against 4, so its average is the more settled of the two. Written reviews point the same way: 95% of TOPLAPapp's written reviews are positive against 69% of Audulus 4's.

UpkeepUpdate frequency

TOPLAPapp ships an update every 49 months, Audulus 4 monthly. The most recent releases landed on September 24, 2026 and October 6, 2026 respectively.

Scorecard7 real differences · 3 level
TOPLAPapp versus Audulus 4: the parameters behind the verdict, then further details
ParameterTOPLAPappAudulus 4
PriceFreeFree
Rating4.8 (4 ratings) — better4.3 (74 ratings)
Positive reviews95.5% of reviews — better69.2% of reviews
Number of ratings474 — better
Update frequencyEvery 49 monthsMonthly — better
AdsNoNo
In-app purchasesNo — betterYes
MonetizationFree — betterFree with in-app purchases
DevicesiPhone, iPodiPhone, iPad, Mac — better
Requires iOS7.0 — better18.0
Further details — not scored
Size0 MB103 MB
Age rating4+4+
DeveloperJoshua ParmenterAudulus LLC

Customer experience

TOPLAPapp

All ratings4 ratings
Positive100.0%
Neutral0.0%
Negative0.0%
Written reviews22 reviews
Positive95.5%
Neutral0.0%
Negative4.5%

Audulus 4

All ratings74 ratings
Positive82.4%
Neutral4.1%
Negative13.5%
Written reviews78 reviews
Positive69.2%
Neutral10.3%
Negative20.5%

Bugs and requests

TOPLAPapp

Not enough reviews yet to summarise bugs or requests.

Audulus 4

Reported bugs

13 issues
  • iOS 18 compatibility issues (app not working)
  • Save presets but no 'Load' button
  • Undo command issues with DAWs
  • CMD+Z causing data loss
  • Opt+drag not duplicating modules
Show 8 more
  • Plugin window not resizable
  • Menu filtering not functioning properly on iPhone
  • Select and Import buttons not working
  • Blank screen on open
  • App freezes on iPad Pro
  • Black screen on launch after update
  • No modules appearing after iOS 18 update
  • Patches not appearing after iOS 18 update

Requested features

7 requests
  • Add 'Load' button for presets
  • Improve DAW integration (Undo, duplicate)
  • Resizable plugin window
  • More modules (FFT/IFFT, granular buffering)
  • Add CC in module
Show 2 more
  • Sync to host as AUv3
  • Make upgrade path clearer from Audulus 3

In-app purchases

None

TOPLAPapp

No in-app purchases

27 purchases

Audulus 4

Subscriptions2
  • Audulus Pro (1 Month)7 Days trial$4.991 Month
  • Audulus Pro (1 Year)7 Days trial$29.991 Year
One-time25
  • 1-shot Sample$1.99
  • P-Train$2.99
  • CLK RS-1$3.99
Show 22 more
  • CG-1 Chord Generator$3.99
  • CLK Clock Generator$4.99
  • MetaEnvelope$4.99
  • Modal Percussion$4.99
  • CLK: TimeWarp$4.99
  • CPR-1$4.99
  • LMT-1$4.99
  • MS-FUNC$5.99
  • CLK SS-516$7.99
  • J-23 Reverb$7.99
  • J-23 Effects$7.99
  • CLK GS-1$7.99
  • Chaos LFO Bundle$7.99
  • ARP-1$7.99
  • CPR-3$7.99
  • SynD-K1$7.99
  • TRIKOR VCO$9.99
  • CLK Tools Bundle$9.99
  • Essential Synth Bundle$9.99
  • VCF Bundle 1$9.99
  • J-23 Space Console$14.99
  • Patch Editing$29.99

Questions

Is TOPLAPapp free?
TOPLAPapp is free to download, with no in-app purchases.
Is Audulus 4 free?
Audulus 4 is free to download, with in-app purchases available.
Which has better reviews, TOPLAPapp or Audulus 4?
TOPLAPapp is rated higher. TOPLAPapp averages 4.8 out of 5 from 4 ratings, while Audulus 4 averages 4.3 from 74 ratings.
Do TOPLAPapp or Audulus 4 have ads?
Neither TOPLAPapp nor Audulus 4 shows ads.
Which is updated more often, TOPLAPapp or Audulus 4?
TOPLAPapp ships an update every 49 months, and Audulus 4 monthly. Most recently, TOPLAPapp was updated on September 24, 2026 and Audulus 4 on October 6, 2026.

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