ReservedRegion on iPhone Duo

What it is

ReservedRegion is the SwiftUI API Apple shipped in iOS 27.1 so custom UI can claim the largest usable area while staying off hardware the system keeps for itself. The UIKit type is UIViewReservedRegion.

Three hardware ideas sit behind the API:

• Outer camera — always present. It can expand into the Dynamic Island when a Live Activity is running.
• Inner camera — reserved while the camera is active.
• Folding region — the hinge. Active while the device is folded; zero width when the device is flat.

Query those as .division when the fold splits usable areas, or as .occlusion when cameras cover pixels.

SwiftUI modifier

Attach .reservedRegion(.systemControls) around custom chrome and pad with the region the system reports — use this when you own the overlay, not to wrap a NavigationStack that already avoids the fold.

ContentView()
    .reservedRegion(.systemControls) { region in
        CustomOverlay()
            .padding(region.insets)
    }

Use this for a floating action button, a custom control strip, or a view drawn on top of content. Do not wrap an entire NavigationStack just to “avoid the fold” — that stack already does.

GeometryProxy

Query GeometryProxy.reservedRegions when you are laying out by hand: .division is how the fold splits usable areas; .occlusion is pixels cameras cover.

• Prefer the reservedRegion modifier when you only need insets for overlay chrome.
• Query .division when columns or grids must split around the hinge.
• Query .occlusion when drawing must miss camera coverage; pass .includeInactive only when a structural choice must stay stable across poses.

GeometryReader { proxy in
    let divisions = proxy.reservedRegions(kind: .division)
    let occlusions = proxy.reservedRegions(kind: .occlusion)
    // ...
}

Use the returned frames to keep columns, grids, or drawing from sitting on the hinge or under a camera.

Inactive regions

Inactive reserved regions are excluded by default — pass .includeInactive only when a structural choice must stay stable across poses, such as an even column count so a grid does not reshuffle when the hinge goes to zero width.

GeometryReader { proxy in
    let divisions = proxy.reservedRegions(
        kind: .division,
        options: .includeInactive
    )
    // Keep a split layout even when the hinge is inactive / zero-width.
}

UIKit

The UIKit counterpart is UIViewReservedRegion, also introduced in iOS 27.1. Apply it to custom UIView chrome — floating buttons, overlay bars, hand-positioned controls — the same way SwiftUI apps use ReservedRegion. Standard UIKit containers already avoid reserved regions; do not rebuild that avoidance on top of UINavigationController or UITabBarController.

What you can skip

You do not need ReservedRegion if you already use NavigationStack, NavigationSplitView, TabView, List, ScrollView, alerts, sheets, or menus — those system containers already avoid reserved regions.

Skip this API for:

• NavigationStack and NavigationSplitView
• TabView
• List and ScrollView
• Alerts, sheets, and menus

Adopt ReservedRegion only where you drew the chrome yourself. Reimplementing fold avoidance on top of system containers fights the layout the system already computed.

Frequently asked questions