Comparison

FormKey vs HarmonyAngel

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

Head to head
About

FormKey

This app is an intuitive MIDI controller that helps musicians improve by using shapes for notes and colors for octaves. Its unique isomorphic keys aid in pattern recognition and chord discovery, making music creation more accessible.

Highlights
  • Shape-based note input
  • Color-coded octaves
  • Isomorphic key layout
  • Pattern recognition aid
  • Chord discovery assistance
  • Future update commitment
Features
Read full description

Unlock your music potential. FormKey is the first music suite that helps you become the musician you've always imagined being, just by using it. INTRODUCING FORM Form is a new way to read and create music. Notes become shapes. Octaves become colors. Duration becomes a simple to read fraction. You can learn to read and play music in minutes. FormKey is the first release of the Form notation language, an open licensed music language designed to create instant music literacy. With the goal being to become a standard you'll see everywhere. THREE MODES: CREATE, LEARN, AND CONTROL • Create mode gives you a 16-track sequencer built on the classic drum machine workflow, modernized for today. Use your own AUv3 plugins or the three we built in to create full tracks from the ground up. • Learn lets you play and read your way through classical pieces while Form teaches you exactly what the music is doing, note by note. • Control turns FormKey into a MIDI controller for your external workflows, so it fits right into the setup you already have. THREE BRAND NEW AUv3 PLUGINS • Tone is a fully interactive subtractive synth that makes synthesis make sense. Every knob and connection is something you can hear and understand, so the architecture of a sound stops being a mystery. • Wave is a file-based sampler that lets you chop audio from your own device into something new. Slicing, shaping, and rearranging samples feel effortless instead of technical. • Pn0 is a modeled piano designed to sound rich while being incredibly simple to use • All 3 work in any host, so the instruments you learn in FormKey come with you wherever you go. SCALE MODE Reshape the keyboard to any of 26 scales, so every note you play stays in key. Choose from: • Major and minor: Major, Natural Minor, Melodic Minor, Harmonic Minor • Modes: Ionian, Dorian, Phrygian, Lydian, Mixolydian, Aeolian, Locrian • Pentatonic and blues: Major Pentatonic, Minor Pentatonic, Blues • Symmetric: Whole Tone, Whole-Half Diminished, Half-Whole Diminished, Augmented Hexatonic • World and exotic: Hungarian Minor, Neapolitan Minor, Byzantine, Enigmatic, Hirajoshi, In Sen, Kumoi, Iwato We've refined the interface across the app, making FormKey easier and more enjoyable to use. Every feature in FormKey is free to try. In celebration of our launch, $14.99 unlocks everything for the life of the app. We hope you love it as much as we do.

About

HarmonyAngel

Features
Read full description

HarmonyAngel is a MIDI and vocal harmony processor for musicians who want one monophonic line to follow the active chord. Choose chord slots on two performance pages, then play from a MIDI controller or the on-screen piano. For every incoming note, HarmonyAngel can generate descending chord tones below it, align voicings to a chord root, preserve slash-chord roots, and forward aftertouch to the generated harmony. Turn on Mic Input to sing into HarmonyAngel. The app performs low-latency monophonic pitch detection locally, uses the detected note to create the same chord-aware MIDI harmony, and provides a live tuner and input-level meter. Premium users can optionally hear pitch-corrected lead vocal and pitch-shifted vocal harmony audio, with selectable pitch detector, pitch shifter, formant, latency, buffer, trigger-level, and trigger-velocity controls. Choose a Jazz Soli style when you need arranged ensemble-style lines instead of simple chord stacking. Built-in Bebop, Smart Soli, Smooth Big Band, Functional Jazz, Barry Harris, Cool Jazz, Quartal Fusion, Minimal Guide Tones, and Altered Dominant styles use the active chord, melody direction, and musical register to produce practical voicings. Premium users can create, validate, import, export, and organize declarative custom styles in the Jazz Soli Library. Use it standalone with CoreMIDI and the built-in sine synth, or load the AUv3 MIDI processor inside a compatible host. Page controls, progression stepping, hold behavior, custom chord types, selectable MIDI ports, channel routing, keyboard range, display transpose, and velocity shaping are available from the performance UI. Highlights: - Two pages of 12 editable chord slots with no-harmony slots - Built-in chord types, slash roots, and named custom chord types - Jazz Soli styles for melody-aware, multi-part jazz voicings - Premium Jazz Soli Library authoring with validated import and export for custom styles - One-page or two-page MIDI control channel slot switching - Progression controls for stepping through saved chord sequences - Full or partial on-screen piano with touch velocity and aftertouch - Harmony count, root alignment, skip-first-harmony, and revoice-on-switch controls - Delta or ratio harmony velocity and aftertouch shaping - Mic Input with local monophonic vocal pitch detection, tuner, and input-level metering - Premium pitch-corrected lead vocal and pitch-shifted vocal harmony audio - Premium single-channel or rotating-channel harmony MIDI output - Premium MIDI input/output port selection and virtual MIDI output port - Hold and panic controls with process/bypass hold modes - Premium AUv3 MIDI processor extension with preservable host state - Optional built-in sine wave synth for quick testing or standalone use HarmonyAngel is designed for keyboardists, singers, composers, producers, worship musicians, live performers, and anyone who wants fast chord-aware harmony from simple MIDI or vocal input. Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/ Privacy Policy: https://bwinnovationtw.github.io/apps/harmonyangel/privacy.html

Screenshots

HarmonyAngel4 screens

Verdict

The call

FormKey and HarmonyAngel are too close to call on the numbers: across 6 compared parameters — price, update cadence, ads and in-app purchases among them — neither pulls far enough ahead to decide it. What separates them is feature set and interface, not measurable difference.

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

Both are free to download. FormKey sells 1 one-off in-app purchase and HarmonyAngel sells 4 in-app purchases, starting at $0.99 per 7 days. Whichever you choose, the download price is not the number that matters.

UpkeepUpdate frequency

FormKey ships an update fortnightly, HarmonyAngel every 4 weeks. The most recent releases landed on October 6, 2026 and October 10, 2026 respectively.

ScorecardNo meaningful differences
FormKey versus HarmonyAngel: the parameters behind the verdict, then further details
ParameterFormKeyHarmonyAngel
PriceFreeFree
Rating4.3 (6 ratings) — better—
Positive reviews50.0% of reviews—
Number of ratings6 — better—
Update frequencyFortnightly — betterEvery 4 weeks
AdsNoNo
In-app purchasesYesYes
MonetizationPaid—
DevicesiPadiPhone, iPad — better
Requires iOS18.617.0 — better
Further details — not scored
Size86 MB7 MB
Age rating4+4+
DeveloperPolyhedraBetter World Studio

In-app purchases

1 purchases

FormKey

One-time1
  • FormKey Full Unlock$14.99
4 purchases

HarmonyAngel

Subscriptions3
  • Weekly Subscription3 Days trial$0.997 Days
  • Monthly Subscription7 Days trial$1.991 Month
  • Yearly Subscription14 Days trial$9.991 Year
One-time1
  • Life-time Purchase$19.99

Questions

Is FormKey free?
FormKey is free to download, with in-app purchases available.
Is HarmonyAngel free?
HarmonyAngel is free to download, with in-app purchases available.
Do FormKey or HarmonyAngel have ads?
Neither FormKey nor HarmonyAngel shows ads.
Which is updated more often, FormKey or HarmonyAngel?
FormKey ships an update fortnightly, and HarmonyAngel every 4 weeks. Most recently, FormKey was updated on October 6, 2026 and HarmonyAngel on October 10, 2026.

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