Turnkey Cashback Service Mobile App Development

A cashback service is the link between the user, the store, and the partner network. If attribution is broken, the business loses up to 30% of commissions. A typical mistake is using the built-in WebView for tracking. An incorrectly chosen transition mechanism leads to losing up to a third of partner commissions, directly impacting service profitability. That's why we pay special attention to choosing the component for opening links: on iOS it's SFSafariViewController, on Android — Chrome Custom Tabs. These components guarantee cookie transfer and correct cashback accrual, minimizing attribution losses. Over 5 years we have delivered 15+ projects and know all the pitfalls. We've helped dozens of clients launch their cashback services and save on lost commissions. Request a consultation for a detailed project estimate.

How Purchase Attribution Works in a Cashback App

Attribution is built on tracking links from partner networks: Admitad, CJ, Impact, or proprietary ones. Step by step:

1. The app opens a tracking link: https://trk.admitad.com/g/xxxxx?uid={userId}
2. The tracker redirects to the store, sets a cookie
3. The user completes a purchase
4. The store sends the conversion to the network with uid
5. The network sends a postback to your server
6. The server accrues cashback to the user with that uid

The transition to the store uses SFSafariViewController (iOS) or Chrome Custom Tabs (Android). Never use the built-in WKWebView: its cookies are isolated and not shared with Safari, leading to up to 30% loss of attribution. Chrome Custom Tabs loads 20% faster than WKWebView and supports shared browser sessions — this increases conversion from clicks to purchases.

Comparison of store opening methods:

For iOS we use SFSafariViewController, for Android — Chrome Custom Tabs.

import SafariServices

func openShopWithTracking(shop: Shop) {
    guard let trackingUrl = buildTrackingUrl(shop: shop, userId: currentUser.id) else { return }
    let safariVC = SFSafariViewController(url: trackingUrl)
    safariVC.preferredControlTintColor = .systemBlue
    present(safariVC, animated: true)
    // Record the transition locally for statistics
    analyticsService.track(.shopOpened(shopId: shop.id))
}

// Android: Chrome Custom Tabs for tracking
val customTabsIntent = CustomTabsIntent.Builder()
    .setShowTitle(true)
    .setColorScheme(CustomTabsIntent.COLOR_SCHEME_LIGHT)
    .build()

customTabsIntent.launchUrl(this, trackingUri)

Contact us for a project evaluation — we'll find the optimal tracking architecture.

Cashback Accrual and Payout

Cashback is stored as an internal user balance. Accrual statuses:

For payouts, we integrate YooKassa Payouts, Tinkoff Payouts API, or MTS Pay — each bank has its specifics. On average, payout implementation takes 1–2 weeks. We guarantee compliance with App Store Review Guidelines (Section 5.1) and Google Play policies.

Store Search and Filtering

The store list is the main screen. Filters: category, cashback size (fixed percentage or amount), newness, popularity. On the backend — full-text search via PostgreSQL tsvector or Elasticsearch. The client debounces requests:

// iOS: search with debounce using Combine
@Published var searchQuery = ""

init() {
    $searchQuery
        .debounce(for: .milliseconds(300), scheduler: RunLoop.main)
        .removeDuplicates()
        .filter { $0.count >= 2 }
        .sink { [weak self] query in
            self?.loadShops(query: query)
        }
        .store(in: &cancellables)
}

Why Trust Our Team with Development?

We have 5+ years of mobile development experience, 15+ published apps, and certifications from App Store and Google Play. We provide full documentation, source code, store access, and training for your team. A cashback service is a complex product with high accountability for attribution, so we use only proven trackers and strictly adhere to platform policies. Get a consultation on your project architecture.

What's Included in the Work (Deliverables)

• Architecture documentation (Tech Stack, Flow Charts)
• Source code for iOS (Swift 5.9+, SwiftUI/UIKit) and Android (Kotlin, Jetpack Compose)
• Access to App Store Connect and Google Play Console with configured certificates
• Integration with partner networks (Admitad, CJ, Impact) and payout providers
• Push notifications (FCM/APNs) with interest-based segmentation
• Team training (2 hours online) and user guide

Time Estimates

Basic version development (catalog, tracking, history) takes 4–6 weeks. Payout implementation takes another 1–2 weeks. Full cycle including backend integration — up to 10 weeks. The cost is calculated individually after analyzing your technical specification. We'll evaluate your project for free – contact us.

Payments in Mobile Apps: In-App Purchase, StoreKit 2, Google Billing, Stripe, RevenueCat

In every monetization project, we balance App Store and Google Play policies, PCI DSS requirements, and purchase verification logic on the backend. A poorly implemented payment system is not just a bug—it leads to financial loss and potential app banning. Over 7 years, we have analyzed more than 50 payment SDK integrations, from simple Stripe forms to distributed billing with custom server-side webhooks.

In-App Purchase: Two Platforms, Two Different APIs

If your app sells digital content or subscriptions, Apple and Google require you to use their payment systems. This is non-negotiable: violating App Store rule 3.1.1 or Google Play Developer Policy results in app removal. Physical goods and offline services are a different story.

StoreKit 2 (iOS 15+)

StoreKit 2 is a complete overhaul of the original StoreKit with async/await API. Product.products(for:), product.purchase(), Transaction.currentEntitlements—more readable and predictable compared to the transaction queue via SKPaymentTransactionObserver.

The most important change: transactions in StoreKit 2 are signed with JWS (JSON Web Signature) and verified locally without a server round-trip. Transaction.verificationResult returns .verified(Transaction) or .unverified(Transaction, VerificationError). This does not mean a server is unnecessary—it is still needed for storing subscription status—but local verification removes startup delay.

StoreKit.AppTransaction verifies the actual app download from the App Store. Required for paid downloads or non-renewing purchases.

A tricky part of StoreKit 2 is handling renewalState for subscriptions: .subscribed, .expired, .inBillingRetryPeriod, .inGracePeriod, .revoked. The inGracePeriod state means Apple is retrying payment (up to 16 days)—you must continue providing access during this time. Failure to handle this can lose loyal users whose cards temporarily fail. Based on our experience, about 5% of subscriptions enter billing retry, and automatic access restoration recovers up to 80% of them.

Google Play Billing Library (v6+)

Google Billing is more complex than StoreKit in terms of scenario handling. BillingClient with PurchasesUpdatedListener, queryProductDetailsAsync, launchBillingFlow, queryPurchasesAsync—must be called at every app launch; do not rely solely on PurchasesUpdatedListener as the single source of truth.

Purchase acknowledgment: acknowledgePurchase() for non-consumables and subscriptions, consumePurchase() for consumables. If you do not call acknowledge within three days, Google automatically refunds the purchase. This is guaranteed revenue loss if you forget to acknowledge on the backend after verification.

ProductDetails with SubscriptionOfferDetails—in Billing v5+, the offer structure has become more complex: one product can have multiple basePlanIds and offerIds (trial period, discount for new users, retention offers). BillingFlowParams.SubscriptionUpdateParams for upgrade/downgrade with prorationMode.

Why Is Server-Side Verification Mandatory?

Never trust only client-side code when unlocking paid content. Client-side verification can be bypassed by modifying the app.

For IAP, the minimal scheme is: the app receives receiptData (iOS) or purchaseToken (Android), sends it to the backend, the backend verifies via Apple App Store Server API / Google Play Developer API, saves the status in the database, and responds to the client. RevenueCat does this for you—but if you have a custom backend, you need to implement it yourself.

Webhooks are more important than they seem. Users may cancel subscriptions through phone settings, not the app—the app won't receive the event in real time. Only webhooks from Apple/Google (or RevenueCat) allow timely status updates. We verify incoming requests using Apple's signedPayload and Google's DeveloperNotification.

How Does RevenueCat Simplify Integration?

Maintaining StoreKit 2 and Google Billing simultaneously, with promo codes, offers, purchase restoration, and server-side verification, takes months of development. RevenueCat handles most of this layer.

RevenueCat is not just a payment SDK. It offers:

• A unified API for iOS and Android (and Stripe for web)
• Server-side verification and subscription status storage
• Webhooks for events (purchase, renewal, cancellation, billing issue)
• Analytics for cohorts, MRR, churn
• A/B testing of offers via Experiments

Purchases.configure(withAPIKey:) at startup, Purchases.shared.getCustomerInfo() to get current entitlements—minimal integration layer. Purchases.shared.purchase(package:) instead of directly calling StoreKit/Billing.

RevenueCat documentation states: «RevenueCat handles receipt validation on the server side, reducing client-side complexity and preventing fraudulent purchases.»

Limitations of RevenueCat: it is paid (free up to $2.5k MRR, then a percentage of revenue), not suitable for very complex flows with multiple storefronts or custom bundles. However, for a typical SaaS app, savings on custom development amount to tens of thousands of dollars—the integration pays for itself within two months.

Stripe in Mobile Apps

Stripe is used for physical goods, services, and B2B payments where IAP is not required by platform policy.

Stripe iOS SDK and Android SDK—PaymentSheet for ready-made payment UI, PaymentSheetFlowController for custom UI with saved cards. Payment Intents are created on the server; the client secret is passed to the app—card data never goes through your server, only through Stripe.

Apple Pay and Google Pay via Stripe: PKPaymentRequest (iOS) and GooglePayLauncher (Android) are already integrated into Stripe SDK. Apple Pay conversion rates are 1.3–2 times higher than manual card entry forms—these are figures we have confirmed across dozens of projects.

Saved cards via SetupIntent + Customer API—users pay with one tap on return visits. Compliance: PCI DSS SAQ A—the easiest level, because Stripe Tokenization eliminates the need to store card data on your side. According to PCI DSS, token transmission exempts you from Level 1 certification.

3DS2 (Strong Customer Authentication) is mandatory for payments in the EU under PSD2. Stripe handles it automatically via PaymentIntent.confirmPayment, but you need to correctly handle the .requiresAction status and return the user to the appropriate screen after authentication.

What Is Included in the Work (Deliverables)

Process and Timeline

We start by clarifying the business model: subscriptions, one-time purchases, consumables, freemium. The architecture depends on this. Testing IAP requires Sandbox accounts (Apple) and License Testers (Google)—this is a separate environment setup.

Apple's Sandbox behaves differently from production: subscriptions renew every 5 minutes instead of monthly, inGracePeriod works differently. It is essential to test scenarios: trial expiration, cancellation, billing retry, refund.

The cost is calculated individually based on the set of tools and complexity of server-side logic. On average, we fit within a budget for a typical integration, but the savings from preventing errors and churn offset this investment within a few months.

Get a consultation for your project—contact us. We will help you choose the optimal payment architecture that passes store reviews and does not break under peak loads.