
Music
Retune
Slow it down without changing the key
People stuck transcribing by ear or practising an instrument because the original tempo is too fast, and anyone who wants language audio at a speed they can actually hear.
When it's useful
A phrase goes by too fast
Drop to 75% or 50% and the pitch stays at the original. Presets from 0.5x to 2x are one tap away.
You need the same few bars again and again
Loop an A–B section. Lift the bass with the equaliser, or thin out the vocal to hear what the band is doing behind it.
The track only exists somewhere on your device
Import from Files, by extracting audio from a video, from your on-device Apple Music library, from the microphone, or from Dropbox.
You want to practise along with a lesson video
Videos can be imported with the picture intact. Slow them down without changing the pitch, and loop a section A–B.
What it does
Pick one on the left to switch to that screen.



Common friction, and how it's solved
"Slowing playback drags the pitch down with it, and the notes stop being the notes"
Speed and pitch move independently. Change one and the other stays put.
"Practice apps pack in so much that the first screen tells you nothing about where to start"
Only speed, pitch and transport are always visible. Loops and EQ live inside a section you open when you want them.
"Every new device means loading all the same tracks in again"
iCloud syncs the tracks, the playlists and the audio files themselves. The destination is your own iCloud — nothing passes through our servers.
What every app I've built shares
No silent network access
Nothing is sent to a developer's server unless you turn it on yourself. No account, no login, no tracking.
Your records stay yours
Everything stays on your device, or in the storage you choose. Turn sync on yourself when you want progress kept in step.
Comes out ready for AI
Export to Markdown, JSON, or CSV and hand it straight to your own AI.
- Version
- 1.0
- Size
- 7MB
- Requires
- iOS 17.0+
- Price
- 無料(耳コピツールは買い切り)
- Released
- 2026-09-19
Get it on the App StoreDownload for Mac
Mac 1.3 (7MB / macOS 14 or later / notarized by Apple). Distributed straight from this site, not through the App Store.
SHA-256: 4ff8058c9f2663209c0699faf96f54c6b02e9b0189eb9608e15a6b43b002baa9
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