Finance v9.100.0
Does Citi Mobile work on iPhone Duo?
It works, but with black bars. Citi Mobile 9.100.0 is built with the iOS 26.5 SDK, so iPhone Duo runs it in a phone-sized window on the inner display.
At a glance
- Inner display (7.6″)
- Black bars
- Outer display (5.4″)
- Works normally
- Built with
- iOS 26.5 SDK
- Version 9.100.0, read Oct 29, 2026
- iPad version
- No
- Phone-only layout today
- Latest version
- v9.100.0
- Oct 27, 2026
- Duo in release notes
- Not yet
About Citi Mobile
Citi Mobile is made by Citibank and first came out on the App Store in January 2009. It has 4,126,864 ratings on the US App Store, averaging 4.9 stars. Version 9.100.0 came out on Oct 27, 2026 and needs iOS 16.0 or later. It's free to download. Among the 25 banking & finance apps we track on the US App Store, 8 already fill the inner display, 4 are partly adapted and 12 still show black bars. By number of ratings, Citi Mobile is #11 of them.
From its App Store listing:
Simpler All Mobile Account*: Open a checking or savings account right from the app without setting foot in a bank branch Card Replacement: Request a new card if your original is lost, stolen or damaged Citi Mobile® Snapshot: Quickly review key account info – without having to sign in every time Zelle®: A fast, fee-free way within the Citi Mobile App to pay and easily split payments with people you…
On the inner display
Apps built with older SDKs are placed in a phone-sized safe area on a black background. Everything works; you just don't get the bigger screen.
In Split View
iPhone Duo is the first iPhone that can show two apps side by side, and every app takes part — including Citi Mobile. 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
App build,
Version 9.100.0 is built with the iOS 26.5 SDK
Apple runs apps built with the iOS 26 SDK or earlier in a phone-sized window on the inner display.
- : Not confirmed yet → Black bars — built with the iOS 26.5 SDK
Latest release notes
Version 9.100.0 · Oct 27, 2026
Thanks for using the Citi Mobile® App! To give you the best experience, we’re constantly improving our app. This update also includes various bug fixes and performance improvements.
Questions
Does Citi Mobile work on iPhone Duo?
It works, but with black bars. Citi Mobile 9.100.0 is built with the iOS 26.5 SDK, so iPhone Duo runs it in a phone-sized window on the inner display.
Does Citi Mobile 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 Citi Mobile 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.
Why does Citi Mobile have black bars on iPhone Duo?
Apps built with the iOS 26 SDK or earlier run in a phone-sized window on the inner display, and iOS 27 builds can still leave some space empty. The bars disappear once the developer rebuilds the app with the iOS 27.1 SDK — you only need to update the app.
When will Citi Mobile fill iPhone Duo's inner display?
When its developer releases an update built with the iOS 27.1 SDK or later. We read the SDK of every new version of Citi Mobile within about a day of its release and update this page.
What can I do about the black bars until then?
Use Citi Mobile on the outer display, where it works like on any iPhone, or put it in Split View next to another app on the inner display so less of the screen goes unused.