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iOS Capabilities

iOS App Clips

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iOS App Clips

An App Clip is a small, lightweight part of your application that is discoverable exactly when the user needs it.

Users can launch an App Clip almost instantly without having to download your full app from the App Store.

They are perfect for frictionless, real-world interactions like renting a scooter, ordering coffee, or paying a parking meter.

The 15MB Limit

Because App Clips are meant to open instantly over a cellular connection, Apple enforces a strict size limit.

Historically, this was 10MB, but for modern iOS versions, the uncompressed binary must be under 15MB.

This means you must carefully strip out unnecessary heavy assets, large SDKs, and unused code from your App Clip target.

How Users Find App Clips

App Clips are designed to bridge the physical and digital worlds. Users can launch them via:

Apple even provides special visually distinct "App Clip Codes" that incorporate both NFC and a camera-scannable design.

Handling Invocations

When a user launches your App Clip, your code receives an NSUserActivity.

This activity contains the URL that triggered the clip, allowing you to deep-link the user to the exact screen they need (e.g., a specific scooter's rental page).

Handling App Clip URLs:

import SwiftUI


struct ContentView: View {
    @State private var scooterID: String = "Unknown"
    var body: some View {
        VStack {
            Text("Renting Scooter: \(scooterID)")
        }
        // This modifier catches the incoming App Clip URL
        .onContinueUserActivity(NSUserActivityTypeBrowsingWeb) { userActivity in
            guard let incomingURL = userActivity.webpageURL else { return }
            // Parse the URL to find the scooter ID
            if let components = URLComponents(url: incomingURL, resolvingAgainstBaseURL: true),
               let queryItems = components.queryItems,
               let id = queryItems.first(where: { $0.name == "id" })?.value {
                self.scooterID = id
            }
        }
    }
}

Sign in with Apple & Apple Pay

The whole point of an App Clip is speed. Forcing a user to type in a credit card or create a new password ruins the experience.

App Clips heavily rely on Sign in with Apple for instant accounts and Apple Pay for instant, secure transactions.

By combining these technologies, a user can walk up to a parking meter and pay within 5 seconds without installing anything!

Exercise

What is the strict maximum uncompressed size limit for an iOS App Clip?

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