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Once

Xeanco LimitedUtilities

View in the App Store
On iPhone Duo

Letterboxed

Once runs in an iPhone-sized window with black bars.

Want Once to fill the inner display? Be the first to ask.

Its latest version is built with the iOS 26.5 SDK,[1] which Apple shows letterboxed on the inner display.[2]

How we know
From the app’s build
Checked on
Version 2.63.0
Build
iOS 26.5 SDK
Latest version
2.63.0, Sep 21, 2026
Status updated

What owners report

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Version history

  1. Version 2.63.0Letterboxed

    iOS 26.5 SDK

    Checked Oct 26, 2026

Sources

  1. App Store build, version 2.63.0

    Built with the iOS 26.5 SDK. Uses none of Apple’s iPhone Duo APIs.

  2. Apple Developer: Prepare your app for iPhone Duo
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