Comparison

Audulus 4 vs Piano Chord Practice

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

Head to head
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

About

Piano Chord Practice

Features
Read full description

A chord practice app designed to make learning piano chords fun. It is made for people who know chord names but cannot quickly play them on the keyboard, or who want to practice not only major and minor chords, but also 7th, 9th, sus, dim, and aug chords. In Practice Mode, you can focus on a wide range of chord types, including major, minor, 7th, sus, dim, aug, 9th, 11th, and 13th chords. In Chord Progression Mode, you can challenge yourself with genre-based progressions such as Pops, Rock, Jazz, R&B, HipHop, House, Lo-Fi, and Future Bass. MIDI keyboards are supported, so you can practice using either the on-screen keyboard or a real keyboard. Learn chord shapes and sounds in a game-like way while checking correct and incorrect answers. A MIDI device is recommended for this app. Available in English and Japanese.

Screenshots

Audulus 44 screens
Piano Chord Practice4 screens

Verdict

The call

The clearest difference is price: Audulus 4 at Free against Piano Chord Practice's $2.99. Audulus 4 also leads on iOS requirement (18.0 vs 26.0). Piano Chord Practice's advantage is in-app purchases (none vs 10) and update cadence (every 5 days vs monthly). On 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

Audulus 4 is free to download; Piano Chord Practice costs $2.99 up front. Audulus 4 sells 10 one-off in-app purchases. Piano Chord Practice asks for nothing beyond the download.

UpkeepUpdate frequency

Audulus 4 ships an update monthly, Piano Chord Practice every 5 days. The most recent releases landed on November 3, 2026 and October 31, 2026 respectively.

Scorecard4 real differences · 6 level
Audulus 4 versus Piano Chord Practice: the parameters behind the verdict, then further details
ParameterAudulus 4Piano Chord Practice
PriceFree — better$2.99
Rating4.3 (73 ratings) — better—
Positive reviews69.2% of reviews—
Number of ratings73 — better—
Update frequencyMonthlyEvery 5 days — better
AdsNoNo
In-app purchasesYesNo — better
MonetizationFree with in-app purchases—
DevicesiPhone, iPad, Mac — betteriPhone, iPad
Requires iOS18.0 — better26.0
Further details — not scored
Size103 MB210 MB
Age rating4+4+
DeveloperAudulus LLCyuji yoshie

Bugs and 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

Piano Chord Practice

Not enough reviews yet to summarise bugs or requests.

In-app purchases

10 purchases

Audulus 4

One-time10
  • 1-shot Sample$1.99
  • CG-1 Chord Generator$3.99
  • J-23 Reverb$7.99
Show 7 more
  • 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
None

Piano Chord Practice

No in-app purchases

Questions

Is Audulus 4 free?
Audulus 4 is free to download, with in-app purchases available.
Is Piano Chord Practice free?
Piano Chord Practice costs $2.99, with no in-app purchases.
Do Audulus 4 or Piano Chord Practice have ads?
Neither Audulus 4 nor Piano Chord Practice shows ads.
Which is updated more often, Audulus 4 or Piano Chord Practice?
Audulus 4 ships an update monthly, and Piano Chord Practice every 5 days. Most recently, Audulus 4 was updated on November 3, 2026 and Piano Chord Practice on October 31, 2026.

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