Comparison

SJ vs RasterFX

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

Head to head
About

SJ

Features
Currently charting
Read full description

SJ-SQUARE is a Super Jupiter–inspired analog polyphonic synthesizer for iPhone. A warm brown chassis and amber glow meet a hands-on module layout: oscillators, filter, envelopes, LFO, and effects — built for playing, not menus. FEATURES • Multi-oscillator panel with wave, octave, and level controls • Filter with resonance, envelope intensity, and key tracking • Filter envelope & amp controls for expressive shaping • LFO, OSC 2 detune / live layer, chorus, delay, and reverb • Unison (1–4 voices), tempo / tap, and scale snap • Full on-screen keyboard with octave shift & range minimap • MIDI input support for external controllers • Built-in presets ready to play • Landscape-optimized performance UI Craft rich pads, biting leads, and stacked unison tones. Tweak cutoff and envelopes in real time, then perform with the keyboard or your MIDI gear. From the maker of KG-SQUARE, JP-SQUARE, and DX-SQUARE — hardware-inspired synth apps for musicians who love hands-on sound design.

About

RasterFX

This app is a playable modular multi-effects processor for music creation. It allows users to build complex audio effect chains, modulate any control with various sources, and perform patches live. Visualizers provide real-time feedback on sound changes.

Highlights
  • Modular multi-effects processor
  • Build custom effect chains
  • Modulate any control
  • Live performance features
  • Real-time visualizers
  • Record and share audio
Features
Read full description

Make any sound move. RasterFX is a playable modular multi-effects processor for iPhone and iPad. Use it standalone with a microphone, an imported audio file or built-in signals — or load it as an AUv3 audio effect in AUM, GarageBand, Logic Pro for iPad, Loopy Pro, Cubasis and other Audio Unit hosts. BUILD YOUR EFFECT CHAIN Choose from Filter, Delay, Drive, Reverb, Grain, Repeat, Motion and Dynamics. Arrange up to six plates in series or split them into parallel A/B paths. Reorder the chain and the sound changes with it. MODULATE ANY CONTROL Patch LFOs, envelope followers, random and chaos sources, step sequencers, MIDI, macros, the XY pad or device tilt to any control. Create up to 16 modulation lines, with live arcs showing exactly how the sound is moving. PERFORM THE PATCH Morph between four snapshots on the XY pad. Turn eight macros. Hold four momentary throws for stutter, sweep, reverse and freeze. RasterFX is built to be played with one hand, not programmed and left alone. GENERATE, LOCK, EVOLVE Nudge a patch, reshape it or roll a new one. Lock the parts you want to keep, undo any result and save the seeds worth returning to. Evolve lets the patch drift over time while staying anchored to the sound you chose. SEE WHAT YOU HEAR Every effect has its own live visualizer. The CRT and halftone interface makes filters, delay taps, grains, dynamics and modulation visible without turning the screen into a wall of meters. RECORD THE RESULT Record the processed output to WAV, rename takes and share them from the app. FREE TO START. PRO ONCE. Free includes all eight effects, all modulation sources, every factory preset, three plates, four modulation lines and 60-second recordings. No ads, account, watermark or reduced audio quality. RasterFX Pro is a one-time purchase — not a subscription. It unlocks six plates, 16 modulation lines, split routing, XY snapshot morphing, Evolve, A/B compare, unlimited recording length and your own saved presets. Your saved sound always plays back exactly as created, even if it uses Pro features; Free limits editing, never playback. Made for headphones, late at night.

Screenshots

SJ1 screens
RasterFX4 screens

Verdict

The call

The clearest difference is price: RasterFX at Free against SJ's $0.49. RasterFX also leads on iOS requirement (17.0 vs 26.5). SJ's advantage is in-app purchases (none vs 1) and chart position (#192 vs unranked). 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

RasterFX is free to download; SJ costs $0.49 up front. RasterFX sells 1 one-off in-app purchase. SJ asks for nothing beyond the download.

Scorecard4 real differences · 6 level
SJ versus RasterFX: the parameters behind the verdict, then further details
ParameterSJRasterFX
Price$0.49Free — better
Rating—5.0 (1 ratings) — better
Number of ratings—1 — better
Update frequencyFortnightly—
AdsNoNo
In-app purchasesNo — betterYes
Monetization—Freemium
Best chart rank#192 — better—
DevicesiPhone, iPadiPhone, iPad
Requires iOS26.517.0 — better
Further details — not scored
Size30 MB5 MB
Age rating4+4+
DeveloperKouki YoshimotoChih Han Lin

In-app purchases

None

SJ

No in-app purchases

1 purchases

RasterFX

One-time1
  • RasterFX Pro$3.99

Questions

Is SJ free?
SJ costs $0.49, with no in-app purchases.
Is RasterFX free?
RasterFX is free to download, with in-app purchases available.
Do SJ or RasterFX have ads?
Neither SJ nor RasterFX shows ads.

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