SUS4 Sketchpad: Song Ideas
Hum it: key, tempo and chord
Free · In-App Purchases
You hummed a chorus in the shower. Get it down before it goes, put the lyric and chords under it, and find it next week by tag, not by scrolling memos.
Hum the melody. Get the key and a chord to start from.
A songwriting sketchpad that captures an idea and works out its key, tempo and root chord.
Everything is stored privately on your device: no cloud library, no account, no sync.
Musical ideas come in moments — a melody you are humming in the kitchen, a chord sequence that surfaced while you were noodling before practice, a lyric fragment that arrived before the tune did. SUS4 Sketchpad is where those ideas become something you can actually work with.
Hum or sing into the mic and the app transcribes the melody to MIDI. From there you can edit, export to your DAW, and build on the idea without having to figure it out from memory. The on-device lyric assist feature — powered by a language model that runs entirely on your iPhone — helps you develop a lyric fragment into a full verse or chorus without opening another app or sending anything to a server.
• Hum-to-MIDI transcription: sing a melody, get editable MIDI
• MIDI sketch editor — adjust notes before you export
• On-device lyric assist, powered by an AI model that never leaves your phone
• MIDI export to any DAW
• Subscribe monthly, or unlock the full SUS4 suite forever: unlimited sketches, lyric assist, chord suggestions, and MIDI export
All AI runs on your device. Your melodies and lyrics stay private.
Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/
Ratings & Reviews
- This app has not received enough ratings or reviews to display an overview.
Stability and performance improvements.
The developer, ThePaulSmith, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Not Collected
The developer does not collect any data from this app.
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Provider
- Paul Smith
- Size
- 21.4 MB
- Category
- Music
- Compatibility
Requires iOS 16.0 or later.
- iPhone
Requires iOS 16.0 or later. - iPad
Requires iPadOS 16.0 or later. - Mac
Requires macOS 13.0 or later and a Mac with Apple M1 chip or later. - Apple Vision
Requires visionOS 1.0 or later.
- iPhone
- Languages
- English
- Age Rating
4+
- 4+
- In-App Purchases
Yes
- SUS4 Sketchpad Lifetime £59.99
- SUS4 All-Access £4.99
- SUS4 Sketchpad Pro Monthly £0.99
- Copyright
- © 2026 4chords Studios