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github-actions[bot] edited this page Apr 29, 2026 · 3 revisions

In-App Purchases (IAP)

PrayCalc uses native in-app purchase APIs on iOS and Android. The implementation uses StoreKit 2 on iOS and Google Play Billing on Android, both via native Flutter plugins.

iOS — StoreKit 2

Plugin: flutter/ios/PrayCalcApp/IAPPlugin.swift

StoreKit 2 is used for all purchase flows. It provides async/await APIs, automatic transaction verification, and built-in receipt validation.

Product IDs are defined in App Store Connect and referenced via StoreKit/Products.storekit in the Xcode project.

Purchase flow

  1. App calls IAPPlugin.loadProducts() — returns available Product objects from StoreKit
  2. User taps purchase — app calls IAPPlugin.purchase(productId)
  3. StoreKit presents the payment sheet
  4. On success, Transaction.currentEntitlement(for:) is polled to verify entitlement
  5. App unlocks the feature and calls Transaction.finish() to clear the queue

Restore purchases

Call IAPPlugin.restorePurchases() — this calls AppStore.sync() which re-fetches the signed transaction history from Apple. Works across device reinstalls.

Subscription management

Users manage subscriptions from the iOS Settings app or via the App Store subscriptions page. The app links there directly from the account screen.

Sandbox testing

Use a Sandbox test account (App Store Connect > Users and Access > Sandbox) to test purchases without real payment. Sandbox purchases expire rapidly (e.g. 1-month subscription = 5 minutes in sandbox).

Android — Google Play Billing

Plugin: flutter/android/app/src/main/kotlin/com/praycalc/app/IAPPlugin.kt

Uses Google Play Billing Library (latest stable). All billing operations run on the main thread via the BillingClient.

Purchase flow

  1. App initialises BillingClient and calls queryProductDetailsAsync() to load SKUs
  2. User taps purchase — app calls launchBillingFlow() with a BillingFlowParams
  3. Google Play presents the payment sheet
  4. On purchase result, app calls queryPurchasesAsync() and acknowledges the purchase server-side
  5. Feature is unlocked and BillingClient.acknowledgePurchase() is called within 3 days (Google requirement)

Restore purchases

Call BillingClient.queryPurchasesAsync(ProductType.SUBS) — returns all active subscriptions tied to the Google account.

Testing

Use the Google Play License Testing accounts (configured in Google Play Console > Setup > License Testing). The test account bypasses real payment and allows testing all purchase states including PURCHASED, CANCELED, PENDING, and ITEM_ALREADY_OWNED.

Ummat+ Features

The following features require an active Ummat+ subscription:

  • Smart home prayer automations
  • TV Command Center (manage connected TVs)
  • Priority adhan notifications
  • Premium adhan voices
  • Ad-free experience

See Smart-Home for the full smart home feature list.

See Also

PrayCalc by Ummat Dev | MIT License

PrayCalc

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