Does RUN4 work on iPhone Duo?
Probably, but it's not confirmed. RUN4 was updated on 26 October 2026 (version 1.1.2), after Apple's iPhone Duo tools came out, but Eugen Schott doesn't mention iPhone Duo. Apps built with Apple's standard components fill the inner screen on their own once rebuilt.
- On iPhone Duo
- Updated, unconfirmed
- Developer
- Eugen Schott
- Category
- Music
- Current version
- 1.1.2 · 26 October 2026
- App Store rating
- 5 out of 5 (1 rating)
- Last checked
How we know
Updated since Apple's iPhone Duo tools came out (5 October 2026), but the developer doesn't mention the Duo. Apps built with Apple's standard components fill the inner screen on their own. See it on the App Store
History on iPhone Duo
- · Updated, unconfirmed (version 1.1.2)
Other Music apps on iPhone Duo
-
音楽 LINE MUSIC 最新の歌や曲・ミュージック多数！LINE MUSIC CORPORATION · MusicUpdated, unconfirmedUpdated 15 October 2026 -
Jフェスrockin'on holdings inc. · MusicNot yetLast update 3 September 2026 -
Amazon MusicAMZN Mobile LLC · MusicUpdated, unconfirmedUpdated 26 October 2026 -
Koala Sampler • Beat MakerMazbox Limited · MusicAdaptedRelease notes, version 2.0.15 -
YouTube MusicGoogle · MusicUpdated, unconfirmedUpdated 25 October 2026 -
SpotifySpotify · MusicUpdated, unconfirmedUpdated 23 October 2026 -
Deck-ManSquircle Apps LLP · MusicAdaptedApple's list, 22 October 2026 -
DeezerDEEZER SA · MusicUpdated, unconfirmedUpdated 21 October 2026
All apps on iPhone Duo in Japan →
Got an iPhone Duo? How does RUN4 look on the inner screen?
No owner report yet for version 1.1.2.
Still looking for the iPhone Duo itself? Restocks sell out within minutes: get an alert the moment one lands near you.
Good to know
Does RUN4 work on iPhone Duo?
Probably, but it's not confirmed. RUN4 was updated on 26 October 2026 (version 1.1.2), after Apple's iPhone Duo tools came out, but Eugen Schott doesn't mention iPhone Duo. Apps built with Apple's standard components fill the inner screen on their own once rebuilt.
Why do some apps have black bars on iPhone Duo?
Because they were built before Apple's iPhone Duo tools. On the inner screen, an app built for an older iOS opens in an iPhone-size window on a black background; one built for iOS 27.0 uses more of it but leaves some space blank; only apps built with the iOS 27.1 SDK, which developers have had since 5 October 2026, use the whole display.
When will RUN4 be adapted to iPhone Duo?
Only Eugen Schott knows. We check RUN4 on the App Store again within about 1 h: this page changes as soon as a new version says it supports iPhone Duo.
Do apps that aren't adapted still work on iPhone Duo?
Yes. Every iPhone app runs on iPhone Duo: one that isn't adapted just doesn't fill the inner screen until its developer updates it.
How we measure
Sources: Apple's list of apps adapted to iPhone Duo (22 October 2026) and each app's App Store record (version, release date, release notes, description). Apple doesn't say which tools an app was built with, so an app stays “Updated, unconfirmed” until its developer says more.