# Contour — Ambient Morph Synth — Drones, textures, pads, MIDI

> Touch-based ambient morphing synthesizer for drones, textures, and pads. (iPhone/iPad app by Chih Han Lin.)

- Source: https://appshunter.io/ios/app/contour-ambient-morph-synth/id6798038727 (this page in markdown: same URL + `.md`)
- Developer: [Chih Han Lin](https://appshunter.io/developer/1800248325)
- Category: Music, Entertainment
- Price: Free with in-app purchases
- Rating: 3.00/5 from 1 App Store ratings · 1 written reviews indexed
- Age rating: 4+
- Requires: iOS 16.0 · 108 MB
- Languages: American English
- Released: 2026-08-18
- Data updated: 2026-08-20
- Monetization: freemium
- User reviews in markdown: https://appshunter.io/ios/app/contour-ambient-morph-synth/id6798038727/reviews.md

## What is Contour?

Contour is an instrument you play by walking.

Four neural decoders sit at the corners of a square. Your finger somewhere in
the middle is a blend of all four, and the square is drawn as a survey sheet.
The contour lines are not decoration. They come from what those four decoders
actually produce, laid out so that equal distances on screen are equal
perceptual distances in sound. Cross a line and the sound has changed by a
measured amount.

THE SHEETS

Eleven of them, each a different set of four corners, each chosen by measuring
the whole library rather than by ear. They are grouped by what the measurement
found:

BRIGHT — HEHUAN, the brightest, where all four corners hold their own.
CONTRAST — BEIYIDUAN, the widest corner spread at 8.2 times.
BREATH — NENGGAO, the breathiest.
DEPTH — MABO, the deepest at 53 dB.
RANGE — YUSHAN, the widest at 66 semitones; JIAMING, the most focused at 17.

They are named after Taiwan's high mountain traverses.

PLAYING IT

Touch the sheet to sound it. The ribbon underneath sets pitch, or send MIDI and
play it from a keyboard. Press harder and the note opens up — the contact patch
of your finger is the dynamic. Hold on empty ground to drop a mark you can come
back to.

The readout above the ribbon tells you where you are while you are there:
brightness, noise, the grid reference, the frequency.

IN A HOST

Contour is also an AUv3 plug-in. It runs in AUM, GarageBand, Cubasis, Logic for
iPad and anything else that hosts Audio Units, with the position automatable as
two parameters and the sheet recallable with your session. The plug-in draws
the same map the app does, laid out for the window a host gives it.

WHAT IS FREE

Three sheets — BEIYIDUAN, NENGGAO and YUSHAN — with the whole instrument: the
map, the ribbon, MIDI, reverb, marks, and the plug-in. No time limit and no
account.

CONTOUR PRO

A single purchase, once, unlocks:

• All eleven sheets
• Recording, straight to a file
• The envelope panel — attack, decay, sustain, release
• Composing sheets of your own from the library, 4,845 combinations of four
  corners, with the map baked for the pitches they share

Requires iOS 16 or later. iPhone and iPad.

## Key features

- Touch-based sound generation
- Perceptual distance mapping
- Eleven distinct sound sheets
- MIDI input and ribbon controller
- AUv3 plugin support
- Recording functionality (Pro)
- Customizable sound sheets (Pro)

## Pricing and in-app purchases

Base price: Free.

**One-time purchases**

| Purchase | Price | Type |
| --- | --- | --- |
| Contour Pro | $6.99 | one-time |


## Recent user reviews (1 of 1)

All indexed reviews: https://appshunter.io/ios/app/contour-ambient-morph-synth/id6798038727/reviews.md

### 3/5 — Close

*2026-08-19*

Sounds great but need the ability to save multiple user sounds. Also the sheets don’t load inside of AUM.

## Frequently asked questions about Contour

### What is Contour?

Contour is a unique musical instrument app that allows you to create ambient sounds, drones, and textures by interacting with a visual interface. Your finger's position on the screen directly influences the sound produced, offering an intuitive and expressive playing experience.

### What sound sheets are available in Contour?

Contour offers eleven distinct sound sheets, each with a unique set of four corners designed to produce different sonic characteristics. These sheets are grouped by qualities like brightness, contrast, breathiness, depth, and range, named after Taiwanese mountain traverses.

### Can I use Contour with a MIDI keyboard?

Yes, Contour supports MIDI input, allowing you to play it from an external keyboard. The ribbon underneath the main interface also serves as a pitch controller, and the contact patch of your finger acts as a dynamic control.

### Is Contour available as a plugin?

Yes, Contour is also available as an AUv3 plugin. It can be used within hosts like AUM, GarageBand, Cubasis, and Logic for iPad, with automatable parameters and session recall capabilities.

### What features are included in the free version of Contour?

The free version of Contour includes three sound sheets (BEIYIDUAN, NENGGAO, and YUSHAN), the full instrument functionality including the map and ribbon, MIDI support, reverb, marks, and the AUv3 plugin. There are no time limits or account requirements.

### What does Contour Pro offer?

Contour Pro is unlocked with a single purchase and provides access to all eleven sound sheets, recording capabilities directly to a file, an envelope panel for attack, decay, sustain, and release, and the ability to compose your own sheets from the library.

### What are the system requirements for Contour?

Contour requires iOS 16 or later and is compatible with both iPhone and iPad devices. The app was last updated on August 18, 2026.

### How does Contour compare to other synthesizers?

Contour distinguishes itself through its unique touch-based playing interface and its focus on ambient soundscapes and textures. Unlike traditional synthesizers, it uses a visual map where perceptual distance directly translates to sonic change, offering a novel approach to sound design.

## Version history (last 1 release)

### 1.0 — 2026-08-18

No release notes.

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All apps by Chih Han Lin: https://appshunter.io/developer/1800248325

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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 2026-08-20.*