Holon vs Scaler EQ
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
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.
- 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
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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™
Scaler EQ
This application offers a unique approach to audio equalization by intelligently adjusting frequencies based on the detected key and scale of your music. It provides both musical enhancements and traditional EQ controls for detailed sound shaping.
- In-key EQ with harmonic band types
- Automatic key and scale detection
- Familiar EQ controls with added color
- Magic Shelf for enhanced low and high frequencies
- Mastering-grade limiters and meters
- Dynamic band control and sidechain input
- Standalone and AUv3 host compatibility
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Following on from the award-winning Scaler music theory plugin, Scaler EQ offers a remarkable new way to EQ with musicality and colour. By detecting the key and scale of your audio and enhancing only note frequencies in key with your song, and reducing only note frequencies that aren’t, Scaler EQ can provide a new spin on working with cuts and boosts, increasing the tonality behind your music and providing new harmonic avenues. And for when you just want a regular, fully-featured, modern EQ, Scaler EQ has you covered with its familiar workflow, large choice of band types, mid/side operation, dynamic bands, peak limiters, and stereo enhancement. You can easily apply classic mixing and mastering techniques used by professionals, with an extra optional musical edge. NOTE: We have designed Scaler EQ for iPad. It works on iPhone too with identical functionality but relies more on the two finger tap to zoom function. -The World’s First In-Key EQ -Simple Key Detection -Musician- and Producer-Friendly Band Types -The Magic Shelf -Mastering Grade Limiters and Meters -All the Mod EQ Cons Main Features: Patent pending musical EQ with harmonic band types that boost in-key frequencies and cut out-of-key frequencies Familiar EQ controls translate to a regular workflow – but one that adds more colour Choice of band types for traditional boost/cut EQ or harmonic EQ Magic Shelf bands deliver punchier low end and smoother highs Simple key detection identifies the key and scale of your audio and sets the EQ’s target scale Scale Switching allows for scale and key changes in your track Dial in dynamics for any band (Threshold, Ratio, Attack, Release) Control any shape dynamically via sidechain input Add or remove scale notes for a specific colour (eg, four-note chords or just fifths) Input And Output Peak Limiters Adjustable input and output levels with peak and RMS metering Create unique EQ responses by combining magic shelves, harmonic filters and cuts Each band can be set to work on stereo, mid or side channels Enhance stereo width and collapse low frequencies to mono Minimum phase, zero latency EQ Standalone and compatible with AUv3 host apps such as Logic Pro, GarageBand, Auria, AUM, and Cubasis. Closable Panels and iOS zoom functions What can Scaler EQ be used for? Music Production: Ideal for musicians and producers looking to enhance the musicality of their tracks by ensuring all instruments are in harmony with the chosen scale. Audio Editing: Simplify EQ processes by targeting and cleaning up frequency bands to remove audio that doesn’t belong and enhance audio naturally present with the chosen scale. Audio Engineering: Dynamically soothe audio by suppressing in-harmonic frequencies or expanding harmonic frequencies using dynamic compression and expansion. Mastering: Place on your master channel to broaden your stereo width, focus your bass, increase loudness, and enhance your mix. Sound Designers: Easily create playable instruments from any recorded sound source using the Sound Design presets and musical resonator FX. DJing: DJs can use it to ensure that the tracks they mix are in harmony by detecting the key and scale whilst balancing the mix of each track. -"Scaler EQ is plugin that offers an innovative way to equalise with musicality and colour. It is a plugin that deserves to be tried by anyone." DJ Mag Italia -"Scaler EQ is a groundbreaking advancement in the world of audio engineering. The harmonic EQ technology is a game-changer." Song Mix Master -"Scaler EQ can make subtle harmonic changes or be a hugely creative plugin, but either way it makes your mixes sound better." Computer Music July 2024 -"Scaler EQ delivers harmonic processing we didn’t know we needed, but once heard, we might just apply it to everything." Music Radar -"Scaler EQ is a valuable tool for musicians, producers and audio professionals. It just might be the only EQ you need going forward’ 24bit Electronic Music Production
Screenshots
Verdict
The clearest difference is price: Holon at Free against Scaler EQ's $12.99. Holon also leads on review sentiment (75% vs 50%) and iOS requirement (12.0 vs 15.0). Scaler EQ's advantage is in-app purchases (none vs 2). On rating, ratings volume, update cadence and 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
Holon is free to download; Scaler EQ costs $12.99 up front. Holon sells 2 one-off in-app purchases. Scaler EQ asks for nothing beyond the download.
On the App Store both sit at effectively the same score — 4.5 for Holon against 4.6 for Scaler EQ. Both are backed by a comparable volume of ratings — 14 and 27 respectively. Written reviews are what separate them: 75% of Holon's written reviews are positive against 50% of Scaler EQ's.
Holon ships an update every 3 months, Scaler EQ every 2 months. The most recent releases landed on September 15, 2026 and October 3, 2026 respectively.
| Parameter | Holon | Scaler EQ |
|---|---|---|
| Price | Free — better | $12.99 |
| Rating | 4.5 (14 ratings) | 4.6 (27 ratings) — better |
| Positive reviews | 75.0% of reviews — better | 50.0% of reviews |
| Number of ratings | 14 | 27 — better |
| Update frequency | Every 3 months | Every 2 months — better |
| Ads | No | No |
| In-app purchases | Yes | No — better |
| Monetization | Paid | Paid |
| Devices | iPhone, iPad, iPod, Apple Watch — better | iPhone, iPad, iPod |
| Requires iOS | 12.0 — better | 15.0 |
| Further details — not scored | ||
| Size | 144 MB | 27 MB |
| Age rating | 4+ | 4+ |
| Developer | Holonic Systems Oy | Scaler Music |
Customer experience
Holon
Scaler EQ
In-app purchases
Holon
- Apple Watch supportFree
- Movesense SupportFree
Scaler EQ
No in-app purchases









