ReadWise — RevenueCat Flutter Integration

A quick practice project I built to learn in-app subscription and payment handling in Flutter using RevenueCat.

I hadn't worked with payments in mobile apps before, so I built a simple news reader with a free/premium tier to get hands-on with the RevenueCat SDK — entitlements, offerings, paywalls, restore purchases, and real-time subscription state.

What's in the app

A content/news reader with two tiers:

• Free — 3 articles per day, general & tech categories
• Premium — unlimited articles, Science, Finance & Exclusive categories

Features

• Free vs Premium feature gating — 3 free articles/day + locked premium categories
• Subscription status & management — real-time entitlement checks, renewal info
• Paywall screen — dynamically loads offerings from RevenueCat dashboard
• Restore purchases — required by App Store & Play Store guidelines
• Real-time listener — subscription state updates across the app instantly

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Setup

1. Install dependencies

flutter pub get

2. Configure RevenueCat

1. Create a free account at app.revenuecat.com
2. Create a new project → add iOS and/or Android app
3. Copy your API keys into lib/services/revenue_cat_service.dart:

   static const String _appleApiKey = 'appl_YOUR_KEY_HERE';
   static const String _googleApiKey = 'goog_YOUR_KEY_HERE';

3. Configure products in RevenueCat dashboard

1. Go to Products → add your App Store / Play Store product IDs
2. Go to Entitlements → create one called premium
3. Attach your products to the premium entitlement
4. Go to Offerings → create a default offering with monthly + annual packages

4. Add native platform setup

Android (android/app/src/main/AndroidManifest.xml):

<uses-permission android:name="com.android.vending.BILLING" />

iOS — No extra config needed. Make sure StoreKit is linked (it is by default).

5. Run the app

flutter run

Testing tip: Use RevenueCat's sandbox environment. On Android use a test account in Google Play Console. On iOS use a Sandbox Apple ID.

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Project Structure

lib/
├── main.dart                          # RC initialization + app entry
├── services/
│   └── revenue_cat_service.dart       # All RevenueCat SDK calls
├── cubit/
│   └── subscription_cubit.dart        # Subscription state management
├── models/
│   └── article.dart                   # Article model + mock data
├── screens/
│   ├── home_screen.dart               # Feed with gating logic
│   ├── paywall_screen.dart            # Dynamic offerings paywall
│   ├── subscription_management_screen.dart
│   └── article_detail_screen.dart
└── widgets/
    ├── article_card.dart              # Card with lock overlay
    └── premium_banner.dart            # Inline upgrade prompt

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Key RevenueCat Concepts Demonstrated

Entitlements

The app uses a single premium entitlement. Rather than checking product IDs directly, entitlements abstract the subscription logic — so adding a new product tier never requires an app update.

customerInfo.entitlements.active.containsKey('premium')

Offerings

Prices and packages are fetched from the RevenueCat dashboard at runtime. This means you can run A/B tests on pricing without releasing a new app version.

final offerings = await Purchases.getOfferings();
final packages = offerings.current!.availablePackages;

CustomerInfo listener

The app registers a real-time listener so subscription state (e.g., a renewal or cancellation) is reflected across all screens immediately — no polling required.

Purchases.addCustomerInfoUpdateListener(_onCustomerInfoUpdated);

Restore purchases

Required by both App Store and Google Play guidelines. Allows users who reinstall the app, switch devices, or reinstall to recover their subscription.

await Purchases.restorePurchases();

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Things I learned

• Entitlements over product IDs — checking entitlements.active instead of hardcoded product strings means you can add new plans without touching app code
• Offerings are dashboard-driven — prices and packages load from RevenueCat at runtime, so you can adjust or A/B test pricing without a release
• CustomerInfo listener — subscribing to real-time updates means the UI reacts immediately to renewals or cancellations, no polling needed
• Restore purchases — this is required by both App Store and Play Store, easy to miss when you're first starting out