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GET /api/v3/apps/1499417636
{
"app_id": 1499417636,
"canonical_url": "https://appcorpus.com/apps/circle-o-fifths-music-theory-1499417636",
"identity": {
"name": "Circle o Fifths: Music Theory",
"slug": "circle-o-fifths-music-theory",
"developer": {
"name": "Tim Mueller",
"url": "https://appcorpus.com/developers/tim-mueller-developer_de9ac7f3c3a83b73f33d8782d9e62ff4"
},
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"last_checked_label": "31 Jul 2026",
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"rating": 4.8,
"rating_count": 1045,
"formatted_price": "$2.99",
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"version": "2.1.1",
"updated": "2026-07-27",
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{
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{
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}
]
},
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{
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}
],
"ratings": [
{
"store": "apple",
"average": 4.8,
"count": 1045,
"market": "us",
"observed_at": "2026-07-31",
"reviews": [
{
"rating": 5,
"title": "Simple and useful.",
"body": "There’s a book called ‘The Chord Wheel’ published by Hal Leonard that illustrates the same concept as this app. While it’s a good book to have on hand it has one important deficiency: it doesn’t show any fingerings or even the notes for the particular chords. For someone who isn’t very familiar with music theory, this can make it difficult to use the book properly, potentially requiring lots of cross referencing, googling, and general research into theory. This app solves that problem by presenting the circle of fifths/chord wheel side by side with sample fingerings for each chord. Simple, effective, and useful. Well worth the trivial cost of the app. Thanks to the developer for making this one.",
"author": "TraxusIV",
"date": "31 Jul 2026"
},
{
"rating": 5,
"title": "Amazing app!",
"body": "This app is amazing! There is just a little mistake you can correct in the next update: the B chord sounds like a suspended chord instead of a major one. Hope you can correct it, but thanks for giving us such a great tool!",
"author": "SInsignares",
"date": "31 Jul 2026"
},
{
"rating": 4,
"title": "Works great, nice reference and tool!",
"body": "Like another review, there was no sound initially, but it started working after I tapped something or it need a little time connect the audio driver, but it started working. My request is to add PARTS (A,B,C,etc.) to the Progressions tab, with loop counters, so we can construct whole songs. Then it would be incredible as a songwriting tool and composition theory machine. General MIDI support would also be nice. The ability to select external MIDI devices for rhythm and tones would also be useful! I’m saving a star for those features. That all said, the price~performance ratio is superb. Buy it!",
"author": "Tekrytor",
"date": "31 Jul 2026"
},
{
"rating": 5,
"title": "Extremely helpful for cord progressions!",
"body": "This is definitely a must if your interested in starting your journey into music theory! So helpful and very user friendly.",
"author": "cdog12344423",
"date": "31 Jul 2026"
},
{
"rating": 2,
"title": "Almost Awesome but Unusable",
"body": "The view port for the app is not dynamic, so on my phone the left and right edges are cut off, making the left and right sides unusable. Developer - to fix, don't set a fixed width OR rotate the circle based on chord selection, such that the selected root chord rotates to the top, thus making the cut off edges not an issue. Til then, wasted $3 - refund please",
"author": "Nate52790",
"date": "31 Jul 2026"
}
]
}
],
"privacy": [
{
"store": "apple",
"declarations": [
{
"title": "Data Not Collected",
"detail": "",
"source": "Developer declared"
}
],
"accessibility": []
}
],
"changes": [
{
"store": "apple",
"version": "1.0",
"released_at": null,
"notes": ""
},
{
"store": "apple",
"version": "1.1",
"released_at": null,
"notes": "Fix for the help button."
},
{
"store": "apple",
"version": "1.1.1",
"released_at": null,
"notes": "Polished a few things"
},
{
"store": "apple",
"version": "1.1.2",
"released_at": null,
"notes": "Now you can re-tap on any chord while it's still playing to restart it!"
},
{
"store": "apple",
"version": "1.1.3",
"released_at": null,
"notes": "Polished a few things."
},
{
"store": "apple",
"version": "1.2",
"released_at": null,
"notes": "This update adds the ability to learn how to play all 36 guitar chords on the circle, just tap and hold! Also added a handy tutorial that walks you through how to use the app. Happy playing!"
},
{
"store": "apple",
"version": "1.2.1",
"released_at": null,
"notes": "Just some polish in this update. Don't forget to check out the new 36 guitar chord charts on the circle, just tap and hold! Also the handy tutorial that walks you through how to use the app. Happy playing!"
},
{
"store": "apple",
"version": "1.2.2",
"released_at": null,
"notes": "The app now plays sounds even when you have your phone on silent mode."
},
{
"store": "apple",
"version": "1.2.3",
"released_at": null,
"notes": "Just some polish in this version."
},
{
"store": "apple",
"version": "1.2.4",
"released_at": null,
"notes": "Polish for the people!"
},
{
"store": "apple",
"version": "1.3",
"released_at": null,
"notes": "Chords tab! Once you pick your key, it's so nice to see all the chords in that key on one screen as you practice/write/play songs. The chords tab is built just for that. Choose your key from the circle, or the chords tab, transpose on the fly, toggle between major/minor keys, and learn and hear those chords!"
},
{
"store": "apple",
"version": "1.3.1",
"released_at": null,
"notes": "Fixed a little bug in the tutorial. Happy playing!"
},
{
"store": "apple",
"version": "1.3.2",
"released_at": null,
"notes": "A little late summer polish. Happy playing!"
},
{
"store": "apple",
"version": "1.3.3",
"released_at": null,
"notes": "A few small bug fixes, and design polish."
},
{
"store": "apple",
"version": "1.3.4",
"released_at": null,
"notes": "Polish and bug fixes"
},
{
"store": "apple",
"version": "1.4",
"released_at": null,
"notes": "The circle fits much better now on large (iPad) and small (iPhone mini) sized devices."
},
{
"store": "apple",
"version": "2.0",
"released_at": null,
"notes": "2.0 is here, and it's got a piano and a chord progression builder! • Toggle between Guitar and Piano — sounds, diagrams, the whole shebang • New Progressions tab: build a chord progression, hit play, pretend you have a band • Strum patterns from Whole all the way to Folk and Rock, plus a built-in metronome to keep you honest • Piano chord diagrams (you know, with actual piano keys) • iPad layout glow-up • Squashed an embarrassing stereo audio bug — both speakers now invited to the party"
},
{
"store": "apple",
"version": "2.0.1",
"released_at": null,
"notes": "• Progressions tab redesign — cleaner one-row controls (Play, BPM, Key, Loop, Metronome, Pattern) • Pick a key once — it now follows you across the Circle, Chords, and Progressions tabs • Bars per chord — tap any chord chip to hold it for 1, 2, 3, or 4 bars • Tap the BPM number to type an exact tempo • Smoother chord progression playback — chord and metronome stay locked together • Reliability fixes for iOS 17 and newer"
},
{
"store": "apple",
"version": "2.0.2",
"released_at": null,
"notes": "A smoother, more polished Circle o Fifths: • Your key now stays in sync everywhere — pick a key on the Chords or Progressions tab and the wheel follows right along. • Tap the 1–7 scale-degree badges on the circle to hear each chord in the current key. • A revamped tutorial now covers Piano mode and Progressions — and only appears on your first launch. • Smoother animations, refined haptics, and new glass-style touches throughout. • Plus a handful of small fixes to make everything feel just right. Enjoying the app? A quick rating means the world to a small indie developer."
},
{
"store": "apple",
"version": "2.1",
"released_at": null,
"notes": "Make Circle o Fifths yours — this update is all about personalization and polish: • 21 color themes — tap the palette to redress the entire app; a few are suspiciously reminiscent of your favorite films, albums, and bands. • Themed chord charts — the guitar and piano chord diagrams match your chosen theme and look crisper than ever. • New key badge — the center of the wheel now shows your current major and relative-minor key, plus its key signature, at a glance."
}
],
"alternatives": [
{
"app_id": 1537057699,
"name": "Solo - Fretboard Visualization",
"url": "https://appcorpus.com/apps/solo-fretboard-visualization-1537057699",
"reason": "Same category + similar ratings"
}
],
"evidence_summary": {
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"level_label": "Live store listing",
"indexable": true,
"last_verified_at": "2026-07-31",
"unknown_fields": [
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],
"sources": [
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},
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"data_cutoff": "31 Jul 2026"
}
}
