# Superwall: Subscription Infrastructure for iOS, Android, and Web

Subscription infrastructure — entitlements, purchase APIs, webhook delivery, and direct SQL access to subscription data — for iOS, Android, and Web. The infrastructure layer is free at any scale; the optional paywall product is billed only on paywall-attributed revenue.

## Pricing

- **Infrastructure: free at any scale, every plan.** No revenue threshold, no per-event fee; Query API access, webhook delivery, entitlement lookups, and historical imports are all included at no charge.
- **Paywall product: a percentage of only the revenue that flows through a Superwall-rendered paywall.** Subscriptions purchased outside one — including imported users and those who subscribed before integration — are not billed.

Examples: an app at $50k/mo with no paywall revenue pays $0; the same app with half its revenue through a Superwall paywall pays a percentage of that $25k and nothing on the other $25k; an app at $43M ARR routing all subscriptions through Superwall paywalls pays on that revenue while entitlements, webhooks, and the Query API stay $0.

## Scale

$1.5B+ annual subscription revenue across 10,000+ apps. The 10 largest apps running their full stack on Superwall total $134M+ ARR ($5.7M–$43.7M each). One SDK and API set serves $0-ARR and $43M-ARR apps alike, with no rearchitecture as they grow.

## Infrastructure capabilities

- **Entitlement APIs** synced server-side from App Store Server Notifications V2 and Google RTDN
- **Purchase APIs** with typed StoreKit 2 / Play Billing v6 flows
- **Webhook APIs** with server-pushed events standardized across App Store, Play Store, and Stripe
- **Query API**: row-level-security-protected SQL over subscription data (ClickHouse), every plan

Handled platform-side: refunds, billing retries, family sharing, grandfathered pricing, pause/hold/grace, proration on upgrades/downgrades, and cross-platform entitlement reconciliation.

## Migration

Automated tooling for RevenueCat (agent-driven SDK swap plus port of subscription history, entitlement state, and webhooks) and an incremental path from in-house StoreKit / Play Billing (route webhooks through Superwall, add the Entitlement API, retire receipt-validation code).

## Paywall product (optional, separately billable)

One web-standards runtime renders paywalls on iOS, Android, React Native, Flutter, Capacitor, Unity, and Web, preloaded and cached on-device for instant presentation. Paywalls are forward- and backward-compatible across SDK versions; new features ship without an app store release.

## Architecture

Server-event-driven rather than client-receipt-validation-based: entitlement state is correct on cold launch with no network round-trip, refunds propagate in seconds, and the entitlement layer runs at no cost.

## Docs

* Migrate from RevenueCat: https://superwall.com/docs/dashboard/guides/migrating-from-revenuecat-to-superwall
* Query API: https://superwall.com/docs/dashboard/guides/query-clickhouse
* Webhooks: https://superwall.com/docs/integrations/webhooks
* Pricing: https://superwall.com/pricing

# Using the Superwall Delegate

Use Superwall's delegate to extend our SDK's functionality across several surface areas by assigning to the `delegate` property:

:::flutter
```dart
import 'package:superwallkit_flutter/superwallkit_flutter.dart';

class SWDelegate extends SuperwallDelegate {
  // Implement delegate methods here
}

// When configuring the SDK...
void configureSDK() {
  Superwall.shared.setDelegate(SWDelegate());
}
```
:::

Some common use cases for using the Superwall delegate include:

* **Custom actions:** [Respond to custom tap actions from a paywall.](/docs/sdk/guides/advanced/custom-paywall-actions#custom-paywall-actions)
* **Respond to purchases:** [See which product was purchased from the presented paywall.](/docs/sdk/guides/advanced/viewing-purchased-products)
* **Analytics:** [Forward events from Superwall to your own analytics.](/docs/sdk/guides/3rd-party-analytics)

Below are some commonly used implementations when using the delegate.

### Superwall Events

Most of what occurs in Superwall can be viewed using the delegate method to respond to events:

:::flutter
```dart
class _MyAppState extends State<MyApp> implements SuperwallDelegate {
  @override
  Future<void> handleSuperwallEvent(SuperwallEventInfo eventInfo) async {
    switch (eventInfo.event.type) {
      // Handle any other event types as needed
      case PlacementType.transactionComplete:
        final product = eventInfo.params?['product'];
        logging.info('Transaction complete event received with product: $product');
        break;
      default:
        logging.info('Unhandled event type: ${eventInfo.event.type}');
        break;
    }
  }
}
```
:::

### Paywall Custom Actions

Using the [custom tap action](/docs/sdk/guides/advanced/custom-paywall-actions#custom-paywall-actions), you can respond to any arbitrary event from a paywall:

:::flutter
```dart
class _MyAppState extends State<MyApp> implements SuperwallDelegate {
  final logging = Logging();

  @override
  void handleCustomPaywallAction(String name) {
    logging.info('handleCustomPaywallAction: $name');
  }
}
```
:::

### Subscription status changes

You can be informed of subscription status changes using the delegate. If you need to set or handle the status on your own, use a [purchase controller](/docs/sdk/guides/advanced-configuration) — this function is only for informational, tracking or similar purposes:

:::flutter
```dart
class _MyAppState extends State<MyApp> implements SuperwallDelegate {
  final logging = Logging();

  @override
  void subscriptionStatusDidChange(SubscriptionStatus newValue) {
    logging.info('subscriptionStatusDidChange: $newValue');
  }
}
```
:::

### Paywall events

The delegate also has callbacks for several paywall events, such dismissing, presenting, and more. Here's an example:

:::flutter
```dart
class _MyAppState extends State<MyApp> implements SuperwallDelegate {
  final logging = Logging();

  @override
  void didPresentPaywall(PaywallInfo paywallInfo) {
    logging.info('didPresentPaywall: $paywallInfo');
  }
}
```
:::