# KeyOmeter > Automatically identifies and displays musical keys using the circle of fifths. (iPhone/iPad app by Mark Carlotto.) - Source: https://appshunter.io/ios/app/keyometer/id567465936 (this page in markdown: same URL + `.md`) - Developer: [Mark Carlotto](https://appshunter.io/developer/293347135) - Category: Music, Entertainment - Price: $2.99 - Rating: 3.00/5 from 3 App Store ratings · 8 written reviews indexed - Age rating: 4+ - Requires: iOS 10.3 · 6 MB - Languages: English - Released: 2012-10-16 - Data updated: 2026-06-10 - Monetization: paid - User reviews in markdown: https://appshunter.io/ios/app/keyometer/id567465936/reviews.md ## What is KeyOmeter? As easily as a thermometer tells you the temperature, KeyOmeter automatically determines and displays the musical key. KeyOmeter operates in the "circle of fifths" -- a visual representation of the 12 tonal centers or keys of the Western chromatic scale. The outer circle displays the twelve major keys, the inner circle shows their relative minors. Most music is not in a single key but modulates from one key to another. KeyOmeter follows and displays changes in key over time in live music. ## Key features - Automatic musical key detection - Circle of fifths visualization - Displays major and relative minor keys - Tracks live music key changes - Visual representation of tonal centers ## Recent user reviews (8 of 8) All indexed reviews: https://appshunter.io/ios/app/keyometer/id567465936/reviews.md ### 4/5 — Yes it does work *2017-06-14, version 2.1* This app is a surprise. A few of us have been experimenting with this app using our own recorded compositions, or playing on a piano and also using songs from the radio. The app is often exactly correct. The app requires a bit of musical knowledge to interpret what it is telling you. We are very happy with this app and use it often. I would appreciate the developer saying a few words about the new audiobus support. I currently do not own the audiobus app and as it costs $10 would like to know exactly what the benefit of this new feature would be to me. I use AUM which is similar to Audiobus, does this mean I can take advantage of the new feature without buying Audiobus? The very short update detail by the developer leaves many questions! ### 1/5 — Doesn't work! *2016-09-08, version 2.0.0* Don't waste your money. ### 1/5 — Very disappointing *2015-07-09, version 2.0.0* Don't waste your money. Like the other reviewer, I couldn't get it to work either. Will quickly delete. ### 4/5 — KeyOmeter *2015-05-09, version 2.0.0* This app does not work! Don't waste your money!!! ### 1/5 — No bueno *2015-01-08, version 1.4* App doesn't work at all. Every track I try fails on import from iTunes. ### 1/5 — Doesn't work *2014-02-01, version 1.4* Doesn't work. Every song we tried to use live music for resulted in A minor. ### 1/5 — Songwriter *2013-09-17, version 1.3* Didn't work well. I thought it gave " The Key" of a chosen song. Seems that when you play the song, that it gives you each chord change, because the key's kept jumping on the app. So it was no help. Never stayed on one key for the duration of the song. ### 5/5 — Works *2013-04-14, version 1.3* Worked in brief validation test. Very helpful to be able to quickly determine how to play along with. Would be nice to see notes detected real time too but looks like he has another app that does that too. ## Frequently asked questions about KeyOmeter ### What is KeyOmeter? KeyOmeter is a music application that automatically identifies and displays the musical key of a piece of music. It uses the circle of fifths to visualize key relationships and can track key changes in live music. ### How does KeyOmeter work? KeyOmeter analyzes music to determine its key, presenting this information visually through the circle of fifths. The outer circle shows major keys, and the inner circle displays their relative minors. ### Can KeyOmeter detect key changes in live music? Yes, KeyOmeter is designed to follow and display changes in musical key over time, making it useful for analyzing live performances or compositions that modulate between keys. ### What is the price of KeyOmeter? KeyOmeter is a paid application, priced at $2.99. There are no in-app purchases or subscriptions required. ### What devices is KeyOmeter available on? KeyOmeter is available for devices with an age rating of 4+. Specific platform compatibility (iOS, Android) is not detailed in the provided data, but it is a mobile application. ### How often is KeyOmeter updated? The latest version of KeyOmeter is 2.1, which was released on June 13, 2017. This indicates that updates may not be very frequent. ### What do users think of KeyOmeter? KeyOmeter has a rating of 3.0 stars based on 3 ratings. This suggests a mixed to average user reception. ### Does KeyOmeter have ads? The provided data does not specify whether KeyOmeter contains advertisements. However, as a paid app, it is less likely to rely heavily on ad revenue. ## Version history (last 1 release) ### 2.1 — 2017-06-13 This app has been updated by Apple to display the Apple Watch app icon. Audiobus 3 compatible. ## Apps similar to KeyOmeter | App | Rating | Price | Category | | --- | --- | --- | --- | | [Four States Fox Sports Radio](https://appshunter.io/ios/app/four-states-fox-sports-radio/id1489358780) | 5.0 (1) | Free | Music | | [无损音乐播放器](https://appshunter.io/ios/app/id1483316840) | 3.0 (2) | $12.99 | Music | | [FM Radio - Local City &Country](https://appshunter.io/ios/app/fm-radio-local-city-and-country/id1489584840) | 4.3 (6) | Free | Music | | [Setlist Carrot - Setlist.fm](https://appshunter.io/ios/app/setlist-carrot-setlistfm/id1481784500) | 3.9 (15) | Free | Music | | [WEBR - The Breeze](https://appshunter.io/ios/app/webr-the-breeze/id1494166960) | 4.9 (79) | Free | Music | | [PEDRO APP](https://appshunter.io/ios/app/pedro-app/id1492774580) | — | Free | Music | ## More apps by Mark Carlotto - [Pitch To Note](https://appshunter.io/ios/app/pitch-to-note/id293347132) - [What Key](https://appshunter.io/ios/app/what-key/id302005959) - [Audio to MIDI](https://appshunter.io/ios/app/audio-to-midi/id320560554) - [KML Map](https://appshunter.io/ios/app/kml-map/id347857461) - [EZ 3-D Photo](https://appshunter.io/ios/app/ez-3-d-photo/id401437046) - [3-D Movie Camera](https://appshunter.io/ios/app/3-d-movie-camera/id410331993) All apps by Mark Carlotto: https://appshunter.io/developer/293347135 --- *Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-06-10.*