Finish Your iOS 26 Migration Now — App Store SDK Requirements Change on April 28, 2026

Uploading to App Store Connect will require builds with Xcode 26 and the iOS 26 SDK starting April 28, 2026. iOS 26 was released in September 2025 — a major update including the Liquid Glass design and Foundation Models framework announced at WWDC25. iOS 27 will be announced at WWDC26 (June 8–12, 2026) and is expected to ship in September 2026. This article lays out the migration order with both versions in mind.

App Store SDK Requirement Schedule

Every year, Apple raises the minimum SDK version required for submissions to App Store Connect.

Source: <https://developer.apple.com/news/upcoming-requirements/>

If you don’t build with the iOS 26 SDK, you won’t be able to upload app updates to App Store Connect. This isn’t about new features — it’s a mandatory requirement to continue delivering updates to existing users.

iOS 26 Migration Priority Order

Get Your Tooling in Order First

Whether you’re working on iOS 26 compliance or early iOS 27 validation, the first blockers are usually build tooling issues rather than OS APIs. Lock down the tooling first.

The most common issue when migrating to Swift 6 mode is concurrency errors around CoreData. Accessing NSManagedObject outside @MainActor now triggers warnings, so the fix is to wrap operations inside context.perform blocks.

actor DataProcessor {
    func process(context: NSManagedObjectContext) async {
        await context.perform {
            // CoreData operations go inside context.perform
        }
    }
}

Behavior Changes in iOS 26 That Are Easy to Trip Over

TLS Minimum Version Change

For apps linked against the iOS 26 SDK, the minimum TLS version for URLSession and Network framework has been raised from 1.0 to 1.2.

If internal systems or external APIs still use legacy TLS settings, apps built with the iOS 26 SDK won’t be able to communicate with them.

// Example allowing legacy TLS (not recommended — temporary workaround only)
let config = URLSessionConfiguration.default
config.tlsMinimumSupportedProtocolVersion = .TLSv10 // triggers a warning
let session = URLSession(configuration: config)

The correct fix is to upgrade the server side to TLS 1.2 or higher. Make sure to check connections made through third-party SDKs as well.

Removal of UIScreen.mainScreen

UIScreen.mainScreen, which had been previously deprecated, has been promoted to deprecated in the iOS 26 SDK. For compatibility with multi-window and iPadOS scene support, screen size should now be obtained from UIWindowScene.

// Before (deprecated)
let screenWidth = UIScreen.main.bounds.width

// After (recommended)
if let scene = UIApplication.shared.connectedScenes
    .first(where: { $0.activationState == .foregroundActive }) as? UIWindowScene {
    let screenWidth = scene.screen.bounds.width
}

Push to Talk Entitlement Change

The com.apple.developer.pushkit.unrestricted-voip.ptt entitlement no longer works with the iOS 26 SDK. Migration to the Push to Talk framework (iOS 16+) is required.

CoreData iCloud Sync Key Removal

Keys like NSPersistentStoreUbiquitousContentNameKey, which were deprecated over 10 years ago for iCloud ubiquitous sync, now cause build errors with the iOS 26 SDK. Migration targets are NSPersistentCloudKitContainer (iOS 13+) or SwiftData (iOS 17+).

Adapting to Liquid Glass Design

Standard UIKit / SwiftUI components (navigation bars, tab bars, sheets, etc.) automatically adapt to the new design. For custom UI with manual drawing, it’s worth visually verifying on a real device how it interacts with background blur and glass effects.

Getting Ahead on iOS 27 (WWDC26: June 8–12, 2026)

WWDC26 runs June 8–12, 2026. As usual, the new OS will be announced on day one with Beta 1 released immediately. iOS 27 is expected to ship in September 2026.

Testing Priority for Simultaneous iOS 26 & 27 Support

Common Pitfalls for Japanese Business Apps

What to Check Before Upgrading

The fastest first step is to do a rough scan for deprecated APIs.

grep -R "UIScreen.mainb|unrestricted-voip.ptt|UbiquitousContentName|UbiquitousContentURL" ./

Running a similar check for TLS-related issues helps catch things you might miss.

grep -R "TLSv10|TLSv11|tlsMinimumSupported|kCFStreamSSLLevel" ./