# KeyFlow: MIDI Scale Filter — Scale filtering for MIDI keys

> Scale filtering for MIDI keys (iPhone/iPad app by Alexandros Dervos.)

- Source: https://appshunter.io/ios/app/keyflow-midi-scale-filter/id6808661128 (this page in markdown: same URL + `.md`)
- Developer: [Alexandros Dervos](https://appshunter.io/developer/885037478)
- Category: Music
- Price: $8.99
- Age rating: 4+
- Requires: iOS 16.0 · 1 MB
- Languages: American English
- Released: 2026-09-24
- Data updated: 2026-10-31

## What is KeyFlow?

KeyFlow filters MIDI notes before they reach your instrument on iPhone and iPad. Choose a root and scale, set Strictness, and play in key. KeyFlow processes MIDI locally; your instrument or music app produces the sound.

FEATURES
- Manual scales, modes and pentatonic scales
- Adjustable Strictness and Allow All Notes
- Auto Detect Scale with a confidence setting
- Adaptive Harmony and Chord Aware filtering
- Test Notes, note counters and All Notes Off
- AUv3 MIDI effect for compatible hosts

BLUETOOTH MIDI
Connect a Bluetooth MIDI keyboard privately inside KeyFlow. The controller's original MIDI input stays inside KeyFlow while the filtered KeyFlow Out is available to other apps. On iPad, this lets you play an instrument in GarageBand while KeyFlow continues routing in the background. A Bluetooth MIDI controller and a compatible receiving instrument app are required for this workflow.

OTHER MIDI INPUTS
KeyFlow can route MIDI from system inputs such as USB keyboards. Choose the input and output in the standalone app. Configure the receiving app to use the filtered KeyFlow Out and avoid routing the original keyboard directly to the instrument. You can also load the AUv3 MIDI effect before an instrument in a compatible host.

Automatic scale and chord estimates depend on the notes you play. Chord Aware adds a configurable 0–50 ms grouping delay. MIDI 2.0 / UMP support is not claimed.

No account, ads or analytics. Available with the same universal purchase as KeyFlow for Mac once both platforms are approved.

## Is KeyFlow safe?

Not enough ratings yet to assess KeyFlow.

## Is KeyFlow legit?

KeyFlow: MIDI Scale Filter appears legitimate, with a few gaps. The AppsHunter Legitimacy Score for KeyFlow is 75 out of 100 points across 7 verification signals from App Store and developer data.


## Version history (last 1 release)

### 1.0 — 2026-09-25

No release notes.

## More apps by Alexandros Dervos

- [L.A. Dance Academy](https://appshunter.io/ios/app/la-dance-academy/id885037475)
- [Pockytap – Expenses in a tap](https://appshunter.io/ios/app/pockytap-expenses-in-a-tap/id6818329832)
- [Pockytap Organizer](https://appshunter.io/ios/app/pockytap-organizer/id6821046178)

All apps by Alexandros Dervos: https://appshunter.io/developer/885037478

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*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 2026-10-31.*