Comparison

Holon vs Decibel John Cage Variations

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

Head to head
About

Holon

This app transforms your movement through cities into a dynamic, real-time musical score. It uses your physical location and activity to generate interactive synth music, encouraging outdoor exploration and turning listeners into performers.

Highlights
  • Human-powered music generation
  • Encourages outdoor activity
  • Zero UI for minimal distraction
  • Environmentally responsive music
  • Real-time synth music creation
  • Optional AirPods and Apple Watch integration
Features
Read full description

Holon makes the city your instrument. It turns your movement in the environment into a synthetic, interactive score that reflects your context, supports your activities and alerts you to changes in the surrounding area. Holon uses physical computing and a geospatial dataset to synthesize music on the iPhone in real time from your data - no streaming or AI involved, just pure DSP and logic. What Holon Does: * Human powered music. Every action generates dynamic, improvised synth music in real time. * Encourages outdoor activities. Holon doesn’t work in your apartment or by shaking your phone around. Move through streets, parks, and transit systems to make the music happen. * Stays out of your way. Zero UI means less screen time, no distractions. * Uses places and spaces to modify the music you make. The environment isn’t background - it’s the score. * The more and further you move, the more things happen in the music. Use your musical agency instead of skipping and swiping. Why Holon Exists:
 Music has been reduced to a commodity and a background activity for consumerism. Holon isn’t here to help you chill when you swipe, scroll and buy more stuff, or improve your focus when working for the Man. Holon is here to break away from the static, one-way relationship of streaming services and to put the human in the loop - yourself. Forget emoting celebrities with their false sincerity, throw overproduced passive soundscapes and statistical algorithms on the dung heap of history. Holon turns listeners into performers and unlocks the musical potential of places. How to Use: * Go outside - Holon needs space to function, just like you. Different districts, parks, bridges, shops, street furniture - all contribute to the musical output. Strolling around your apartment or shaking your phone won’t do. * Put the phone in your pocket or on your dashboard. * Walk, run, drive - the world is now the interface, space is the machine. * Use the big button in the middle to power Holon off when not in use - Auditory AR can be a battery-intensive process! * Optional Apple AirPods support for head-controlled musical interactions! * Optional Apple Watch support for heart rate-synced music (biofeedback) *the Watch app may take a moment to install* Requirements:
 * Available in over 1000 regions in more than 100 countries. * Check coverage or request a new area at holonic.systems/holon. * Best experienced with headphones. Ensure adequate battery level for extended use. * A data plan is required to access our geospatial engine but use of data is low. Holon: Become part of the circuit and… Become Sound™

About

Decibel John Cage Variations

Features
Read full description

The Decibel John Cage Variations app guides performers through a realisation of the complete John Cage Variations. It generates a series of animated and standard graphic notation scores in real time that allow the works to be easily interpreted while staying true to the aleatoric nature of the originals. The app can be networked between multiple iPads for use by an ensemble. (For more information, see http://www.decibelnewmusic.com/the-complete-john-cage-variations-project.html) The app is designed to be used in conjunction with Cage's scores, and is released in conjunction with the John Cage Trust and Peter's Edition.

Screenshots

Holon4 screens

Verdict

The call

The clearest difference is price: Holon at Free against Decibel John Cage Variations's $2.99. Holon also leads on device support (4 vs 1) and iOS requirement (12.0 vs 15.6). Decibel John Cage Variations's advantage is in-app purchases (none vs 2) and update cadence (every 5 weeks vs every 3 months). On ads 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

Holon is free to download; Decibel John Cage Variations costs $2.99 up front. Holon sells 2 one-off in-app purchases. Decibel John Cage Variations asks for nothing beyond the download.

UpkeepUpdate frequency

Holon ships an update every 3 months, Decibel John Cage Variations every 5 weeks. The most recent releases landed on October 19, 2026 and October 25, 2026 respectively.

Scorecard5 real differences · 5 level
Holon versus Decibel John Cage Variations: the parameters behind the verdict, then further details
ParameterHolonDecibel John Cage Variations
PriceFree — better$2.99
Rating4.5 (14 ratings) — better—
Positive reviews75.0% of reviews—
Number of ratings14 — better—
Update frequencyEvery 3 monthsEvery 5 weeks — better
AdsNoNo
In-app purchasesYesNo — better
MonetizationPaid—
DevicesiPhone, iPad, iPod, Apple Watch — betteriPad
Requires iOS12.0 — better15.6
Further details — not scored
Size144 MB3 MB
Age rating4+4+
DeveloperHolonic Systems OyMonash University

In-app purchases

2 purchases

Holon

One-time2
  • Apple Watch supportFree
  • Movesense SupportFree
None

Decibel John Cage Variations

No in-app purchases

Questions

Is Holon free?
Holon is free to download, with in-app purchases available.
Is Decibel John Cage Variations free?
Decibel John Cage Variations costs $2.99, with no in-app purchases.
Do Holon or Decibel John Cage Variations have ads?
Neither Holon nor Decibel John Cage Variations shows ads.
Which is updated more often, Holon or Decibel John Cage Variations?
Holon ships an update every 3 months, and Decibel John Cage Variations every 5 weeks. Most recently, Holon was updated on October 19, 2026 and Decibel John Cage Variations on October 25, 2026.

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