---
name: dpearson2699/storekit
source: https://app.decimal.ai/s/dpearson2699-storekit@1/SKILL.md
source_sha256: 5e563bcba9ad
---

# StoreKit 2 In-App Purchases and Subscriptions

Implement in-app purchases, subscriptions, paywalls, and StoreKit testing using
StoreKit 2. Use the modern Swift-based `Product`, `Transaction`,
`PurchaseAction`, `StoreView`, and `SubscriptionStoreView` APIs. Avoid original
In-App Purchase APIs (`SKProduct`, `SKPaymentQueue`) unless legacy OS support
requires them.

StoreKit views initiate purchases automatically. For custom controls, use
`PurchaseAction` in SwiftUI, `purchase(confirmIn:options:)` in UIKit/AppKit, and
`product.purchase(options:)` on watchOS.

## Contents

- [Product Types](#product-types)
- [Loading Products](#loading-products)
- [Purchase Flow](#purchase-flow)
- [Transaction.updates Listener](#transactionupdates-listener)
- [Entitlement Checking](#entitlement-checking)
- [SubscriptionStoreView (iOS 17+)](#subscriptionstoreview-ios-17)
- [StoreView (iOS 17+)](#storeview-ios-17)
- [Subscription Status Checking](#subscription-status-checking)
- [Restore Purchases](#restore-purchases)
- [App Transaction (App Purchase Verification)](#app-transaction-app-purchase-verification)
- [Purchase Options](#purchase-options)
- [SwiftUI Purchase Callbacks](#swiftui-purchase-callbacks)
- [Common Mistakes](#common-mistakes)
- [Review Checklist](#review-checklist)
- [References](#references)

## Product Types

| Type | Enum Case | Behavior |
|---|---|---|
| **Consumable** | `.consumable` | Used once, can be repurchased (gems, coins) |
| **Non-consumable** | `.nonConsumable` | Purchased once permanently (premium unlock) |
| **Auto-renewable** | `.autoRenewable` | Recurring billing with automatic renewal |
| **Non-renewing** | `.nonRenewing` | Time-limited access without automatic renewal |

## Loading Products

Define product IDs as constants. Fetch products with `Product.products(for:)`.

```swift
import StoreKit

enum ProductID {
    static let premium = "com.myapp.premium"
    static let gems100 = "com.myapp.gems100"
    static let monthlyPlan = "com.myapp.monthly"
    static let yearlyPlan = "com.myapp.yearly"
    static let all: [String] = [premium, gems100, monthlyPlan, yearlyPlan]
}

let products = try await Product.products(for: ProductID.all)
for product in products {
    print("\(product.displayName): \(product.displayPrice)")
}
```

## Purchase Flow

Prefer StoreKit views for standard paywalls because they initiate purchases,
restore purchases, and display policy controls. For custom SwiftUI purchase
buttons, prefer `PurchaseAction` from the environment. Use direct
`product.purchase(options:)` for watchOS, and use `purchase(confirmIn:options:)`
for UIKit or AppKit confirmation. Always handle every `PurchaseResult`, verify
before access, deliver durably, then finish.

```swift
@Environment(\.purchase) private var purchase

func purchaseProduct(_ product: Product) async throws {
    let result = try await purchase(product, options: [
        .appAccountToken(userAccountToken)
    ])
    switch result {
    case .success(let verification):
        let transaction = try checkVerified(verification)
        await deliverContent(for: transaction)
        await transaction.finish()
    case .userCancelled:
        break
    case .pending:
        // Ask to Buy or deferred approval: show pending UI, no unlock yet.
        showPendingApprovalMessage()
    @unknown default:
        break
    }
}

func checkVerified<T>(_ result: VerificationResult<T>) throws -> T {
    switch result {
    case .verified(let value): return value
    case .unverified(_, let error): throw error
    }
}
```

## Transaction.updates Listener

Start at app launch, not when a paywall appears. Catches purchases from other
devices, Family Sharing changes, renewals, Ask to Buy approvals, refunds,
revocations, and unfinished transactions Apple emits once immediately after
launch. Keep the task retained for the app lifetime.

```swift
@main
struct MyApp: App {
    private let transactionListener: Task<Void, Never>

    init() {
        transactionListener = Self.listenForTransactions()
    }

    var body: some Scene {
        WindowGroup { ContentView() }
    }

    static func listenForTransactions() -> Task<Void, Never> {
        Task(priority: .background) {
            for await result in Transaction.updates {
                guard case .verified(let transaction) = result else { continue }
                await StoreManager.shared.updateEntitlements()
                await transaction.finish()
            }
        }
    }
}
```

## Entitlement Checking

`Transaction.currentEntitlements` emits non-consumables, active or grace-period
auto-renewable subscriptions, and the latest non-renewing subscription
transaction—including finished ones. It excludes consumables and refunded or
revoked products. Track consumable fulfillment separately, and apply the app's
expiration policy to non-renewing subscriptions before granting access.

```swift
@Observable
@MainActor
class StoreManager {
    static let shared = StoreManager()
    var purchasedProductIDs: Set<String> = []
    var isPremium: Bool { purchasedProductIDs.contains(ProductID.premium) }

    func updateEntitlements() async {
        var purchased = Set<String>()
        for await result in Transaction.currentEntitlements {
            if case .verified(let transaction) = result,
               transaction.revocationDate == nil {
                if transaction.productType == .nonRenewing,
                   transaction.expirationDate.map({ $0 <= .now }) ?? true {
                    continue
                }
                purchased.insert(transaction.productID)
            }
        }
        purchasedProductIDs = purchased
    }
}
```

### SwiftUI .currentEntitlementTask Modifier

```swift
struct PremiumGatedView: View {
    @State private var state: EntitlementTaskState<VerificationResult<Transaction>?> = .loading

    var body: some View {
        Group {
            switch state {
            case .loading: ProgressView()
            case .failure: PaywallView()
            case .success(.some(.verified(let transaction))) where transaction.revocationDate == nil:
                PremiumContentView()
            case .success:
                PaywallView()
            }
        }
        .currentEntitlementTask(for: ProductID.premium) { state in
            self.state = state
        }
    }
}
```

## SubscriptionStoreView (iOS 17+)

Built-in SwiftUI view for subscription paywalls. Handles product loading,
purchase UI, and restore purchases automatically.

```swift
SubscriptionStoreView(groupID: "YOUR_GROUP_ID")
    .subscriptionStoreControlStyle(.prominentPicker)
    .subscriptionStoreButtonLabel(.multiline)
    .storeButton(.visible, for: .restorePurchases)
    .storeButton(.visible, for: .redeemCode)
    .subscriptionStorePolicyDestination(url: termsURL, for: .termsOfService)
    .subscriptionStorePolicyDestination(url: privacyURL, for: .privacyPolicy)
    .onInAppPurchaseCompletion { product, result in
        if case .success(.success(.verified(let transaction))) = result {
            await deliverContent(for: transaction)
            await transaction.finish()
        }
    }
```

### Custom Marketing Content

Use the container background and header patterns in
[SubscriptionStoreView Control Styles](references/storekit-advanced.md#subscriptionstoreview-control-styles).

### Hierarchical Layout

Use `SubscriptionOptionGroup`, `SubscriptionOptionSection`, or
`SubscriptionPeriodGroupSet` to organize iOS 18+ options; see
[Subscription Group Management](references/storekit-advanced.md#subscription-group-management).

## StoreView (iOS 17+)

Merchandises multiple products with localized names, prices, and purchase buttons.

```swift
StoreView(ids: [ProductID.gems100, ProductID.premium], prefersPromotionalIcon: true)
    .productViewStyle(.large)
    .storeButton(.visible, for: .restorePurchases)
    .onInAppPurchaseCompletion { product, result in
        if case .success(.success(.verified(let transaction))) = result {
            await deliverContent(for: transaction)
            await transaction.finish()
        }
    }
```

### ProductView for Individual Products

```swift
ProductView(id: ProductID.premium) { iconPhase in
    switch iconPhase {
    case .success(let image): image.resizable().scaledToFit()
    case .loading: ProgressView()
    default: Image(systemName: "star.fill")
    }
}
.productViewStyle(.large)
```

## Subscription Status Checking

```swift
func checkSubscriptionActive(groupID: String) async throws -> Bool {
    let statuses = try await Product.SubscriptionInfo.status(for: groupID)
    for status in statuses {
        guard case .verified = status.renewalInfo,
              case .verified = status.transaction else { continue }
        if status.state == .subscribed || status.state == .inGracePeriod {
            return true
        }
    }
    return false
}
```

### Renewal States

| State | Meaning |
|---|---|
| `.subscribed` | Active subscription |
| `.expired` | Subscription has expired |
| `.inBillingRetryPeriod` | Payment failed, Apple is retrying |
| `.inGracePeriod` | Payment failed but access continues during grace period |
| `.revoked` | Apple refunded or revoked the subscription |

## Restore Purchases

StoreKit 2 handles restoration via `Transaction.currentEntitlements`. Add a
restore button or call `AppStore.sync()` explicitly.

```swift
func restorePurchases() async throws {
    try await AppStore.sync()
    await StoreManager.shared.updateEntitlements()
}
```

On store views: `.storeButton(.visible, for: .restorePurchases)`

## App Transaction (App Purchase Verification)

Verify the legitimacy of the app installation. Use for business model changes
or detecting tampered installations (iOS 16+).

```swift
func verifyAppPurchase() async {
    do {
        let result = try await AppTransaction.shared
        switch result {
        case .verified(let appTransaction):
            let originalVersion = appTransaction.originalAppVersion
            let purchaseDate = appTransaction.originalPurchaseDate
            // Migration logic for users who paid before subscription model
        case .unverified:
            // Potentially tampered -- restrict features as appropriate
            break
        }
    } catch { /* Could not retrieve app transaction */ }
}
```

## Purchase Options

```swift
// App account token for server-side reconciliation
try await product.purchase(options: [.appAccountToken(UUID())])

// Consumable quantity
try await product.purchase(options: [.quantity(5)])

// Simulate Ask to Buy in sandbox
try await product.purchase(options: [.simulatesAskToBuyInSandbox(true)])
```

## SwiftUI Purchase Callbacks

```swift
.onInAppPurchaseStart { product in
    await analytics.trackPurchaseStarted(product.id)
}
.onInAppPurchaseCompletion { product, result in
    if case .success(.success(.verified(let transaction))) = result {
        await deliverContent(for: transaction)
        await transaction.finish()
    }
}
.inAppPurchaseOptions { product in
    [.appAccountToken(userAccountToken)]
}
```

## Common Mistakes

### 1. Not starting Transaction.updates at app launch

```swift
// WRONG: No listener -- misses renewals, refunds, Ask to Buy approvals
@main struct MyApp: App {
    var body: some Scene { WindowGroup { ContentView() } }
}
// CORRECT: Start listener in App init (see Transaction.updates section above)
```

### 2. Forgetting transaction.finish()

```swift
// WRONG: Never finished -- reappears in unfinished queue forever
let transaction = try checkVerified(verification)
unlockFeature(transaction.productID)

// CORRECT: Deliver durably, then finish. If delivery fails, do not finish yet.
let transaction = try checkVerified(verification)
try await recordDelivery(transaction)
await transaction.finish()
```

### 3. Ignoring verification result

```swift
// WRONG: Using unverified transaction -- security risk
let transaction = verification.unsafePayloadValue

// CORRECT: Verify before using
let transaction = try checkVerified(verification)
```

### 4. Using original In-App Purchase APIs in new StoreKit 2 code

```swift
// AVOID: Original In-App Purchase APIs
let request = SKProductsRequest(productIdentifiers: ["com.app.premium"])
SKPaymentQueue.default().add(payment)

// PREFERRED: StoreKit 2
let products = try await Product.products(for: ["com.app.premium"])
let result = try await product.purchase()
```

### 5. Not checking revocationDate

```swift
// WRONG: Grants access to refunded purchases
if case .verified(let transaction) = result {
    purchased.insert(transaction.productID)
}

// CORRECT: Skip revoked transactions
if case .verified(let transaction) = result, transaction.revocationDate == nil {
    purchased.insert(transaction.productID)
}
```

### 6. Hardcoding prices

```swift
// WRONG: Wrong for other currencies and regions
Text("Buy Premium for $4.99")

// CORRECT: Localized price from Product
Text("Buy \(product.displayName) for \(product.displayPrice)")
```

### 7. Not handling .pending purchase result

```swift
// WRONG: Silently drops pending Ask to Buy
default: break

// CORRECT: Explain approval is pending; unlock only after Transaction.updates
case .pending:
    showPendingApprovalMessage()
```

### 8. Checking entitlements only once at launch

```swift
// WRONG: Check once, never update
func appDidFinish() { Task { await updateEntitlements() } }

// CORRECT: Re-check on Transaction.updates AND on foreground return
// Transaction.updates listener handles mid-session changes.
// Also use .task { await storeManager.updateEntitlements() } on content views.
```

### 9. Missing restore purchases button

```swift
// WRONG: No restore option -- App Store rejection risk
SubscriptionStoreView(groupID: "group_id")

// CORRECT
SubscriptionStoreView(groupID: "group_id")
    .storeButton(.visible, for: .restorePurchases)
```

### 10. Subscription views without policy links

```swift
// WRONG: No terms or privacy policy
SubscriptionStoreView(groupID: "group_id")

// CORRECT
SubscriptionStoreView(groupID: "group_id")
    .subscriptionStorePolicyDestination(url: termsURL, for: .termsOfService)
    .subscriptionStorePolicyDestination(url: privacyURL, for: .privacyPolicy)
```

## Review Checklist

- [ ] `Transaction.updates` listener starts at app launch in App init
- [ ] All transactions verified before granting access
- [ ] `transaction.finish()` called only after durable content delivery
- [ ] Revoked/refunded transactions excluded and entitlement state updated
- [ ] `.pending` result shows Ask to Buy/deferred-approval feedback
- [ ] Restore purchases button visible on paywall and store views
- [ ] Terms of Service and Privacy Policy links on subscription views
- [ ] Prices shown using `product.displayPrice`, never hardcoded
- [ ] Subscription terms (price, duration, renewal) clearly displayed
- [ ] Free trial states post-trial pricing clearly
- [ ] No original In-App Purchase APIs (`SKProduct`, `SKPaymentQueue`) unless legacy OS support requires them
- [ ] Product IDs defined as constants, not scattered strings
- [ ] StoreKit tests cover promotional offers, win-back, offer codes, Ask to Buy, renewals, refunds, and revocations
- [ ] Entitlements re-checked on Transaction.updates and app foreground
- [ ] Server-side validation uses `jwsRepresentation` if applicable
- [ ] Consumables delivered and finished promptly
- [ ] Transaction observer types and product model types are `Sendable` when shared across concurrency boundaries

## References

- See [references/app-review-guidelines.md](references/app-review-guidelines.md) for IAP rules (Guideline 3.1.1), subscription display requirements, and rejection prevention.
- See [references/storekit-advanced.md](references/storekit-advanced.md) for subscription control styles, offer management, testing patterns, and advanced subscription handling.
- For submission, privacy, metadata, screenshots, and rejection-risk audits use `app-store-review`.
- For keyword, screenshot-caption, ranking, and conversion strategy use `app-store-optimization`.
- Official Apple docs: [Choosing a StoreKit API](https://sosumi.ai/documentation/storekit/choosing-a-storekit-api-for-in-app-purchases), [Transaction.updates](https://sosumi.ai/documentation/storekit/transaction/updates), [Transaction.currentEntitlements](https://sosumi.ai/documentation/storekit/transaction/currententitlements),
  [SubscriptionStoreView](https://sosumi.ai/documentation/storekit/subscriptionstoreview), and [PurchaseAction](https://sosumi.ai/documentation/storekit/purchaseaction).