Comparison

Robot Butter vs Nulltrack

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

Head to head
About

Robot Butter

This audio effect app creates dynamic soundscapes by blending animated modulation, adaptive reverb, and digital textures. It offers a fast, playable interface with direct control over key parameters and tempo-synced movement for evolving sound design.

Highlights
  • AUv3 audio effect for iPhone, iPad, and macOS
  • Animated modulation engine
  • Adaptive reverb stage
  • Tempo-synced LFO matrix
  • Digital texture effects
  • Built-in user manual
  • Factory and user presets
Read full description

Robot Butter is a creative AUv3 audio effect for compatible hosts on iOS & iPadOS. It blends animated modulation, adaptive reverb, tempo-aware movement, and digital texture into one fast, playable interface. At the core is the Robot engine, where Actuator, Viscosity, and Controller create the main motion and character of the signal. That signal then feeds Butter, an adaptive reverb stage designed to intelligently stay musical while responding to the effective movement of the Robot section. The result can move from focused width and pulse to washed ambience, strange motion, and unstable experimental color. The Chipset section extends the sound with a built-in assignable LFO matrix and a post-reverb System Bus reduction stage. Run the LFO freely in Hz or lock it to musical divisions for host-synced movement, then route it to key Robot or Butter controls for evolving motion. Add System Bus for subtle grain or push it harder for sharper, crushed digital edge. Robot Butter is designed to stay immediate. The interface gives you direct control over modulation, blend, depth, reverb shape, output mix, and motion timing without pushing you into a complicated modulation environment. A built-in user manual inside the standalone app includes overview pages, parameter explanations, quick-start guidance, glossary entries, MIDI notes, and troubleshooting help, with scrollable section pills that keep longer labels readable. Factory presets and user presets make it easy to jump from polished mix enhancement to stylized movement and aggressive sound design. Features: - Robot modulation engine with Actuator, Viscosity, Controller, and gain staging - Butter adaptive reverb with Churn, Emulsion, and Culture controls - Built-in LFO matrix with free or tempo-synced timing - Assignable LFO destinations across Robot and Butter parameters - System Bus sample-rate reduction stage for animated digital texture - Imaging modes including Mono, Wide, Ping, and Drift when stereo processing is available - Factory presets covering vocals, guitars, bass, keys, synths, drums, utility, and experimental categories - User preset save, recall, and delete support - Comprehensive built-in in-app user manual with quick-start, glossary, and troubleshooting sections - MIDI Learn, Host Learn support, and default CC mappings for hands-on control - Optional MIDI CC broadcast for compatible host-routing workflows - Host tempo sync with straight, dotted, and triplet divisions Use Robot Butter for vocal movement, guitar widening, synth pulse, drum bus animation, ambient wash design, or aggressive lo-fi modulation chains. It is built to move quickly from musical enhancement to animated destruction while keeping the workflow focused and playable.

About

Nulltrack

This mobile digital audio workstation offers a unique, grid-based approach to music creation, inspired by classic trackers. It includes built-in synths, a sampler, extensive modulation options, and mixing tools.

Highlights
  • AUv3 plugin support
  • Two built-in synthesizers
  • Built-in sampler
  • Extensive modulation options
  • Mixing features with track faders
  • Groove tables for swing/playback
  • Pattern locking to scales
Read full description

Nulltrack! It's null when you start and a track when you finish! Nulltrack is a tracker and digital audio workstation app for your phone. A different way to make music inspired by LSDJ and the Dirtywave M8. Features: AUv3 plugin support - bring your external synths and effects into your track! Two built-in synthesizers -- A versatile two-oscillator Basic Synth and a feature-rich Bass Synth. A built-in sampler -- record your own samples with your phone's microphone, load your own, or use the built-in samples, set loop points, slice, reverse, etc. Modulation -- Modulate nearly anything with LFOs, AHD / ADSR / drum envelopes, velocity, randomness, and key tracking, filter, panning, and more. Mixing Features -- track faders with solo and mute, 13 built-in effects, sidechain compression Sends -- share effects between tracks Customize your swing/playback with groove tables! Lock your patterns to a built-in scale! ...and much more! New to trackers? They're a fast, grid-based way to write music. Try it out! No ads, no subscription, no in-app-purchases, and no account needed.

Screenshots

Robot Butter4 screens
Nulltrack4 screens

Verdict

The call

The clearest difference is price: Nulltrack at $7.99 against Robot Butter's $14.99. Nulltrack also leads on update cadence (every 9 days vs monthly). Robot Butter's advantage is device support (4 vs 1). On review sentiment, ads, in-app purchases and monetization model 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

Robot Butter costs $14.99 and Nulltrack $7.99 up front. Neither carries in-app purchases, so what you see is what you pay.

UpkeepUpdate frequency

Robot Butter ships an update monthly, Nulltrack every 9 days. Both last shipped on November 5, 2026.

Scorecard3 real differences · 7 level
Robot Butter versus Nulltrack: the parameters behind the verdict, then further details
ParameterRobot ButterNulltrack
Price$14.99$7.99 — better
Rating5.0 (2 ratings) — better—
Positive reviews100.0% of reviews100.0% of reviews
Number of ratings2 — better—
Update frequencyMonthlyEvery 9 days — better
AdsNoNo
In-app purchasesNoNo
MonetizationPaidPaid
DevicesiPhone, iPad, Mac, Vision Pro — betteriPhone
Requires iOS17.017.0
Further details — not scored
Size7 MB17 MB
Age rating4+4+
DeveloperChristian ThompsonDECTET LLC

Customer experience

Robot Butter

All ratings2 ratings
Positive100.0%
Neutral0.0%
Negative0.0%
Written reviews1 reviews
Positive100.0%
Neutral0.0%
Negative0.0%

Nulltrack

Written reviews1 reviews
Positive100.0%
Neutral0.0%
Negative0.0%

In-app purchases

None

Robot Butter

No in-app purchases

None

Nulltrack

No in-app purchases

Questions

Is Robot Butter free?
Robot Butter costs $14.99, with no in-app purchases.
Is Nulltrack free?
Nulltrack costs $7.99, with no in-app purchases.
Do Robot Butter or Nulltrack have ads?
Neither Robot Butter nor Nulltrack shows ads.
Which is updated more often, Robot Butter or Nulltrack?
Robot Butter ships an update monthly, and Nulltrack every 9 days. Most recently, Robot Butter was updated on November 5, 2026 and Nulltrack on November 5, 2026.

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