Comparison

ChordPolyPad vs RX

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

Head to head
About

ChordPolyPad

This app is a versatile MIDI chord player that allows users to create and play complex chord sets. It offers extensive customization for pads, MIDI controls, and chord generation, functioning as a standalone app or an AUv3 MIDI effect plugin.

Highlights
  • Standalone app and AUv3 MIDI effect plugin
  • 128 pads per preset
  • Customizable X/Y MIDI controllers
  • Advanced random chord generator
  • Internal and external MIDI support
  • Chord filtering and quantizing
  • Preset manager with in-app purchases
Features
Read full description

"ChordPolyPad" is a MIDI chords player that lets you create chord sets using a large internal library, any custom combination of notes, or randomly generated chords. Each preset contains either 8 groups of 16 pads or 2 groups of 64 pads, for a total of 128 pads. In addition to playing chords, each pad can generate customizable MIDI controls on its horizontal and vertical axes, allowing expressive real-time modulation. "ChordPolyPad" can be used as a standalone application or as an AUv3 MIDI effect plug-in. The app supports full internal and external MIDI input and output. An internal sound bank is included for immediate use. The AUv3 MIDI effect plug-in supports multiple instances. A compatible host is required and must support the Audio Unit v3 (AUv3) MIDI effect format. Hosts supporting AUv3 MIDI effect on iOS: Logic Pro, Cubasis, Beatmaker, AUM, Audiobus, NanoStudio, Auria Pro, apeMatrix. Hosts supporting AUv3 MIDI effect on macOS: Logic Pro 10.7 or later. Features: • Standalone application and AUv3 MIDI effect plug-in • 8 groups of 16 pads or 2 groups of 64 pads per preset (128 pads) • Assignable MIDI port and MIDI channel for each pad • Customizable X/Y controller per pad • Per-note velocity control for each chord • Strumming configuration per pad • Copy and paste for pads and groups • Drag and drop chords directly from the library • Chord filtering and quantizing based on the selected scale • Predefined scales and possibility to create custom scales • Advanced random chord generator with diverse musical moods featuring voice leading and context-aware harmonic progressions for naturally flowing compositions • Stop "Audio Background" automatically after inactivity (15 min, 30 min, 1 h, 2 h, or never) • Internal sound bank • Receive MIDI notes and control from external devices • Send MIDI to a virtual port usable as MIDI input by other "Core MIDI" compatible apps • Preset manager with support for in-app purchase packs • "Program Change" support • Preset sharing support by "AirDrop", "Mail", "Messages", and other supported services • Native iCloud support • "iCloud Drive" support in the "Files" app on iOS and "Finder" on macOS • Full support for "Windowed Apps" mode on iPad • Undo/Redo Supported MIDI connections: • Virtual "Core MIDI" connections between apps • Any compatible MIDI interface • MIDI over Wi-Fi • MIDI over Bluetooth

About

RX

Features
Read full description

Play the wind synth you know with a whole new set of sounds. Warm woodwind tones for a soft ballad, bright synth leads for a bold solo. RX-79 is a breath synthesizer that turns your wind controller and iPhone or iPad into a full sound module. Saxophonist SJsax shaped every sound and every response by actually playing it. [Find the right sound for every song] 41 built-in sounds. 14 acoustic sounds including soprano, alto and baritone sax, clarinet, oboe, flute, trumpet, euphonium and harmonica, and 27 electric sounds including brass, leads and basses. Play the same melody in many different moods. Tap the preview button in the sound list to hear a sound even without a controller. [Fit it to your breath] Adjust breath sensitivity, response curve, attack and decay, and set breath noise, tonguing and note-to-note connection to match your playing style. [Make it your own] Shape each sound with brightness, resonance, drive, vibrato, delay and reverb. Save the settings you like to the USER list and give them names. Saved sounds stay on this device. [SJ PACK: 10 signature sounds, sold separately] Extra sounds that carry SJsax's playing feel. Before buying, you can play each sound yourself for 30 seconds. Note: SJ PACK is an in-app purchase sold separately from the app (one-time purchase). [Connection] Connect a USB MIDI wind controller. RX-79 responds to breath (CC2, CC11, aftertouch), pitch bend and vibrato (CC1). Depending on the ports and power needs of your controller and iPhone or iPad, you may need a separate cable or adapter, such as a USB camera adapter. Sound plays even with the silent switch on, and you can play along with backing tracks from other apps. No internet connection required. No personal data is collected. Connection and support https://sjsax.com/rx79/

Screenshots

ChordPolyPad3 screens
RX4 screens

Verdict

The call

The clearest difference is price: RX at $9.99 against ChordPolyPad's $17.99. RX also leads on update cadence (weekly vs every 2 months). On ads, in-app purchases, device support and iOS requirement 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

ChordPolyPad costs $17.99 and RX $9.99 up front. ChordPolyPad sells 3 one-off in-app purchases and RX sells 1 one-off in-app purchase. Whichever you choose, the download price is not the number that matters.

UpkeepUpdate frequency

ChordPolyPad ships an update every 2 months, RX weekly. The most recent releases landed on November 1, 2026 and October 29, 2026 respectively.

Scorecard2 real differences · 8 level
ChordPolyPad versus RX: the parameters behind the verdict, then further details
ParameterChordPolyPadRX
Price$17.99$9.99 — better
Rating4.6 (51 ratings) — better—
Positive reviews92.1% of reviews—
Number of ratings51 — better—
Update frequencyEvery 2 monthsWeekly — better
AdsNoNo
In-app purchasesYesYes
MonetizationFree with in-app purchases—
DevicesiPhone, iPad, iPod, Mac — betteriPhone, iPad, iPod
Requires iOS15.015.0
Further details — not scored
Size54 MB25 MB
Age rating4+4+
DeveloperLaurent Colsonsung ju KIM

In-app purchases

3 purchases

ChordPolyPad

One-time3
  • Retro Pop$4.99
  • Clubwave$4.99
  • Liminal Spaces$4.99
1 purchases

RX

One-time1
  • SJ PACK$5.99

Questions

Is ChordPolyPad free?
ChordPolyPad costs $17.99, and also offers in-app purchases.
Is RX free?
RX costs $9.99, and also offers in-app purchases.
Do ChordPolyPad or RX have ads?
Neither ChordPolyPad nor RX shows ads.
Which is updated more often, ChordPolyPad or RX?
ChordPolyPad ships an update every 2 months, and RX weekly. Most recently, ChordPolyPad was updated on November 1, 2026 and RX on October 29, 2026.

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