In-App Purchases Integration (Unity Plugin)

The iOS Billing SDK is a straightforward solution for implementing Catappult billing. Its Unity Plugin provides a simple interface for Unity games to communicate with the SDK. It comprises a Billing client that integrates with AppCoins Wallet, enabling you to retrieve your products from Catappult and facilitate the purchase of those items.

In Summary

The billing flow in your application with the Plugin is as follows:

  1. Add the AppCoins Unity Plugin;
  2. Query your In-App Products;
  3. User wants to purchase a product;
  4. Application starts the purchase and the Plugin handles it, returning the purchase status and validation data on completion;
  5. Application gives the product to the user.


  1. Unity 2019.4 or later.
  2. iOS 17.4 or higher.

Step-by-Step Guide


  1. Add AppCoins Unity Plugin
    In Unity, add the plugin from the latest release available on the repository to your Assets folder.


Now that you have the Plugin set-up you can start making use of its functionalities.

  1. Check AppCoins Billing Availability
    The AppCoins Billing will only be available on devices in the European Union with an iOS version equal to or higher than 17.4 and only in applications distributed through the Aptoide iOS App Store. Therefore, before attempting any purchase, you should check if the SDK is available by calling AppCoinsSDK.Instance.IsAvailable().

    var isAvailable = await AppCoinsSDK.Instance.IsAvailable();
    if (isAvailable) 
      // make purchase
  2. Query In-App Products
    You should start by getting the In-App Products you want to make available to the user. You can do this by calling Product.products.
    This method can either return all of your Catappult In-App Products or a specific list.

    1. AppCoinsSDK.Instance.GetProducts()

      Returns all application Catappult In-App Products:

      var products = await AppCoinsSDK.Instance.GetProducts();
    2. AppCoinsSDK.Instance.GetProducts(skus)

      Returns a specific list of Catappult In-App Products:

      var products = await AppCoinsSDK.Instance.GetProducts(new string[] { "coins_100", "gas" });
  3. Purchase In-App Product
    To purchase an In-App Product you must call the function AppCoinsSDK.Instance.Purchase(sku, payload). The Plugin will handle all of the purchase logic for you and it will return you on completion the result of the purchase. This result is an object with the following properties:

    1. Success: bool
    3. Error: string

    In case of success the application will verify the transaction’s signature locally. After this verification you should handle its result:

    1. If the purchase is verified you should consume the item and give it to the user.
    2. If it is not verified you need to make a decision based on your business logic, you either still consume the item and give it to the user, or otherwise the purchase will not be acknowledged and we will refund the user in 24 hours.

    In case of failure you can deal with different types of errors.

    You can also pass a Payload to the purchase method in order to associate some sort of information with a specific purchase. You can use this for example to associate a specific user with a Purchase: gas.purchase(payload: "User123").

    var purchaseResponse = await AppCoinsSDK.Instance.Purchase("gas", "User123");
    if (purchaseResponse.State == AppCoinsSDK.PURCHASE_STATE_SUCCESS)
      var response = await AppCoinsSDK.Instance.ConsumePurchase(purchaseResponse.PurchaseSku);
      if (response.Success)
          Debug.Log("Purchase consumed successfully");
          Debug.Log("Error consuming purchase: " + response.Error);
  4. Query Purchases
    You can query the user’s purchases by using one of the following methods:

    1. AppCoinsSDK.Instance.GetAllPurchases()

      This method returns all purchases that the user has performed in your application.

      var purchases = await AppCoinsSDK.Instance.GetAllPurchases();
    2. AppCoinsSDK.Instance.GetLatestPurchase(string sku)

      This method returns the latest user purchase for a specific In-App Product.

      var latestPurchase = await AppCoinsSDK.Instance.GetLatestPurchase("gas");
    3. AppCoinsSDK.Instance.GetUnfinishedPurchases()

      This method returns all of the user’s unfinished purchases in the application. An unfinished purchase is any purchase that has neither been acknowledged (verified by the SDK) nor consumed. You can use this method for consuming any unfinished purchases.

      var unfinishedPurchases = await AppCoinsSDK.Instance.GetUnfinishedPurchases();


  1. Distribution
    To test the SDK integration during development, you'll need to set the installation source for development builds, simulating that the app is being distributed through Aptoide. This action will enable the SDK's isAvailable method.
    Follow these steps in Xcode:

    1. In your target build settings, search for "Marketplaces".

    2. Under "Deployment", set the key "Marketplaces" or "Alternative Distribution - Marketplaces" to "".

    3. In your scheme, go to the "Run" tab, then navigate to the "Options" tab. In the "Distribution" dropdown, select "".

      For more information, please refer to Apple's official documentation:

  2. Purchase

    To test your integration, you will need to make purchases to verify that the integration is set up correctly. Follow these steps:

    1. Obtain your testing Wallet address by calling AppCoinsSDK.Instance.GetTestingWalletAddress().
    2. Contact the Aptoide team and provide them with the address obtained in the previous step.
    3. The Aptoide team will transfer AppCoins Credits (APPC-C) to the provided address.
    4. Complete purchases using AppCoins Credits (APPC-C) to validate your integration.

    🚧 WARNING: Do not delete the application from your testing device. Deleting the application will result in the deletion of your AppCoins Wallet Address, and any AppCoins Credits stored in the Wallet will be lost.

Classes Definition and Properties

The Unity Plugin integration is based on three main classes of objects that handle its logic:


ProductData represents an in-app product.


  • Sku: String - Unique product identifier. Example: gas
  • Title: String - The product display title. Example: Best Gas
  • Description: String? - The product description. Example: Buy gas to fill the tank.
  • PriceCurrency: String - The user’s geolocalized currency. Example: EUR
  • PriceValue: String - The value of the product in the specified currency. Example: 0.93
  • PriceLabel: String - The label of the price displayed to the user. Example: €0.93
  • PriceSymbol: String - The symbol of the geolocalized currency. Example: €


PurchaseData represents an in-app purchase.


  • UID: String - Unique purchase identifier. Example: catappult.inapp.purchase.ABCDEFGHIJ1234
  • Sku: String - Unique identifier for the product that was purchased. Example: gas
  • State: String - The purchase state can be one of three: PENDING, ACKNOWLEDGED, and CONSUMED. Pending purchases are purchases that have neither been verified by the SDK nor have been consumed by the application. Acknowledged purchases are purchases that have been verified by the SDK but have not been consumed yet. Example: CONSUMED
  • OrderUID: String - The orderUid associated with the purchase. Example: ZWYXGYZCPWHZDZUK4H
  • Payload: String - The developer Payload. Example: 707048467.998992
  • Created: String - The creation date for the purchase. Example: 2023-01-01T10:21:29.014456Z


This class is responsible for general purpose methods.