Productivity · v4.2
Does Fantastical Calendar work on iPhone Duo?
Not confirmed yet. Fantastical Calendar runs normally on iPhone Duo's outer display, but there's no reliable report yet of how it looks on the inner display.
At a glance
- Inner display (7.6″)
- Not confirmed yet
- Outer display (5.4″)
- Works normally
- Split View
- Supported
- Every app, automatically
- iPad version
- Yes
- Layout already handles big screens
- Latest version
- v4.2
- Sep 14, 2026
- Duo in release notes
- Not yet
On the inner display
iPhone Duo shows each app in one of three ways depending on which SDK it was built with: letterboxed with black bars (iOS 26 or earlier), expanded with some empty space (iOS 27), or full screen (iOS 27.1 and later). We don't yet know which applies here.
Fantastical Calendar already ships an iPad version, so its layout already copes with larger screens. That gives its developer a head start on iPhone Duo's inner display, which reports the same regular size class as an iPad.
In Split View
iPhone Duo is the first iPhone that can show two apps side by side, and every app takes part — including Fantastical Calendar. Open it on the inner display, then add a second app next to it. You can save the pair and come back to it later.
Duo-specific features
None confirmed yet. Duo-specific features include side toolbars, layouts that react to the fold, and content on the outer display while the app is open inside.
Evidence & history
No public evidence yet. iPhone Duo ships on October 23, 2026; if you have one, tell us how Fantastical Calendar looks — a screenshot helps.
Latest release notes
Version 4.2 · Sep 14, 2026
- Added support for Siri AI to work with Fantastical calendars - Added the ability to set invitee options on Microsoft 365 events - Added the ability to ignore an invite notification for all events in a series - Improved search to handle different punctuation variants - Improved de-duplication of recent locations - Improved the reliability of Calendar Mirroring when using calendars from your device's accounts - Improved Calendar Mirroring and Openings so canceled events are no longer included - Improved moving timed tasks off Todoist so the due date no longer changes unexpectedly - Improved email ingest by adding support for tasks - Improved MCP results so mirrored events are no longer included - Fixed an issue where the event list would reset to the top after scrolling - Fixed an issue where removing a reminder time would also remove the reminder location - Fixed an issue where removing a reminder location would also remove the reminder due date - Fixed an issue where moving certain tasks to Todoist would lose the reminder time - Fixed an issue where the color of delegated calendars on Microsoft 365 accounts could not be edited - Fixed an issue where days with an all-day event wouldn't show up in Up Next - Fixed an issue where deleting specific instances of certain repeating events on Google accounts would fail - Fixed a crash when selecting a recent location - Fixed an issue where repeating events would be mirrored as separate individual events when using local calendars -
Questions
Does Fantastical Calendar work on iPhone Duo?
Not confirmed yet. Fantastical Calendar runs normally on iPhone Duo's outer display, but there's no reliable report yet of how it looks on the inner display.
Does Fantastical Calendar work on the outer display?
Yes. iPhone Duo's 5.4-inch outer display behaves like a regular iPhone screen, so every iPhone app works there as usual.
Can I use Fantastical Calendar in Split View on iPhone Duo?
Yes. On iPhone Duo every app can be placed side by side with another app on the inner display — developers don't need to opt in. How comfortable it feels at half width depends on the app's layout.
Will Fantastical Calendar have black bars on iPhone Duo?
It depends on the version of Apple's SDK the current build of Fantastical Calendar uses: iOS 26 or earlier means black bars, iOS 27 means mostly filled, iOS 27.1 means full screen. We'll update this page as soon as there's evidence.