A pocket synth with eight chord keys on the cover and a loop station when open
Does Octal: Pocket Synth work on iPhone Duo?
Yes, the developer says so: Octal 1.0 is made for iPhone Duo, with the whole synth on the cover and a loop station above the chord keys when open.
- Developer claimedThe developer, Goodhart, in its press kit and the App Store description: closed, the cover holds the whole instrument; open, a track station and an instrument selector sit on the other half. Version 1.0 came out on the App Store on October 15, 2026.
Adapted for the fold
- Closed · Outer display
The whole instrument on the cover
Closed, the maker's image shows the sound-shaping bead beside eight chord keys, with playback and recording controls above. The App Store description says the cover holds the whole instrument.
- Open · Inner display
A loop station above the chord pad
Open and turned upright, the maker's film shows the instrument wheel and eight loop lanes above the chord pad and the sound-shaping bead. The keys light up and the lane patterns change as it plays.
About Octal: Pocket Synth
Octal is a pocket synth built around eight chord keys and a sound-shaping bead, made by Ryan Ellis under the Goodhart name. Version 1.0 runs on iPhones with iOS 26 or later, and its App Store description names iPhone Duo support: closed, the cover holds the whole instrument; open, a loop station and an instrument selector sit above the chord keys.
Evidence reviews
What we checked, when, and what the evidence establishes. Each record preserves the support label at that check.
· Developer media reviewed
Developer claimed · iphone-duo
Looked at the maker's full-size screenshots of the cover and the open screen, and at frames across the 26.87-second film of the open screen. The cover shows chord keys and a bead; open and upright, the layout adds an instrument wheel and loop lanes above them.
App version: Not recorded in this evidence.
The press kit does not show whether the media were captured in the Duo simulator or on a device, and no app version is visible in it. No build was tested, so sound, the fold transition, the microphone, MIDI and export are unchecked. The current US App Store version is 1.0.
View reviewed evidence ↗
On the ideas wall
All ideasOctal: open the synth into a two-part loop station
by Ryan Ellis
Ryan Ellis's Octal puts its chord keys and a sound-shaping bead on the cover. Open and turned upright, the maker's promotional film adds an instrument wheel and loop lanes above the pad. The film isn't said to be a Duo capture.
Related guides
The best iPhone Duo apps so far (October 2026)
The apps worth installing on day one, from Apple's four launch partners to indie apps whose developers have shown a real iPhone Duo layout, picked for what they do when you open the phone.
Do your apps work on iPhone Duo? What happens before they're updated
Every iPhone app opens on iPhone Duo, but only updated ones fill the inner display. What an app looks like before its developer adapts it, how to tell which are ready, and which popular apps have said so.
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Sources: Octal press kit (goodhart.dev) · Octal on the App Store (apps.apple.com)
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