External Purchase Link Types

External Purchase Link (iOS)#

iOS-specific feature for redirecting users to an external website for payment using Apple's StoreKit ExternalPurchase API. Available from iOS 17.4+ (notice sheet) and iOS 18.2+ (custom links).

Result of presentExternalPurchaseLinkIOS. iOS only — wraps ExternalPurchaseLink.open(url:) (Apple docs).

Native references: Apple · StoreKit ExternalPurchase · External purchase entitlement

Important: External purchase links bypass StoreKit completely. No purchaseUpdatedListener will fire. You must implement deep links and server-side verification.

External Purchase APIs#

API	Description	Availability
`canPresentExternalPurchaseNoticeIOS`	Check if external purchase notice sheet can be presented	iOS 17.4+
`presentExternalPurchaseNoticeSheetIOS`	Present Apple's compliance notice sheet (required before external purchase)	iOS 17.4+
`presentExternalPurchaseLinkIOS`	Open external purchase URL in Safari	iOS 18.2+

Types#

ExternalPurchaseNoticeResultIOS

Name	Type	Summary
`result`	`ExternalPurchaseNoticeAction`	User action on the notice sheet (`continue` or `dismissed`)
`error`	`string?`	Optional error message if presentation failed
`externalPurchaseToken`	`string?`	External purchase token returned when `result === 'continue'`. Report to Apple's External Purchase Server API.

ExternalPurchaseLinkResultIOS

Name	Type	Summary
`success`	`boolean`	Whether the user completed the external purchase flow
`error`	`string?`	Optional error message if presentation failed

ExternalPurchaseCustomLinkTokenResultIOS#

Returned by getExternalPurchaseCustomLinkTokenIOS (iOS 18.1+).

Name	Type	Summary
`token`	`string`	Token to send to Apple's External Purchase Server reporting API.
`error`	`string?`	Populated when token creation fails.

ExternalPurchaseCustomLinkNoticeResultIOS#

Returned by showExternalPurchaseCustomLinkNoticeIOS (iOS 18.1+).

Name	Type	Summary
`continued`	`boolean`	Whether the user chose to continue to the external purchase.
`error`	`string?`	Populated when the sheet failed to present.

swift

// Result from presenting external purchase link
struct ExternalPurchaseLinkResultIOS {
    let success: Bool
    let error: String?
}

// Result from presenting notice sheet (iOS 17.4+)
struct ExternalPurchaseNoticeResultIOS {
    let result: ExternalPurchaseNoticeAction
    let error: String?
    // External purchase token returned when result == .continue
    let externalPurchaseToken: String?
}

// User action on notice sheet
enum ExternalPurchaseNoticeAction: String {
    case `continue` = "continue"
    case dismissed = "dismissed"
}

External Purchase Flow#

The external purchase flow requires 3 steps for Apple compliance:

Check availability - Verify the device supports external purchase
Present notice sheet - Show Apple's required disclosure
Open external link - Redirect to your payment page

Complete Example#

swift

import OpenIap

@available(iOS 18.2, *)
func handleExternalPurchase(externalUrl: String) async {
    do {
        // Step 1: Check if external purchase is available
        let canPresent = try await OpenIapModule.shared.canPresentExternalPurchaseNoticeIOS()
        guard canPresent else {
            print("External purchase not available on this device")
            return
        }

        // Step 2: Present Apple's compliance notice sheet
        let noticeResult = try await OpenIapModule.shared.presentExternalPurchaseNoticeSheetIOS()
        guard noticeResult.result == .continue else {
            print("User dismissed the notice sheet")
            return
        }

        // Step 3: Open external purchase link
        let linkResult = try await OpenIapModule.shared.presentExternalPurchaseLinkIOS(externalUrl)
        if linkResult.success {
            print("User redirected to external payment")
            // Implement deep linking to handle return from payment
        } else if let error = linkResult.error {
            print("Failed: \(error)")
        }
    } catch {
        print("External purchase error: \(error)")
    }
}

Requirements#

Requirement	Details
Platform	iOS 17.4+ (notice sheet), iOS 18.2+ (custom links)
Entitlement	App must have StoreKit external purchase entitlement from Apple
Deep Linking	Implement deep linking for app return flow after payment
Verification	Handle purchase verification on your backend (no StoreKit receipt)

Android alternative: For Android, use isBillingProgramAvailableAndroid, launchExternalLinkAndroid, and createBillingProgramReportingDetailsAndroid.