BillingConstants for Google Play

BillingConstants.cs

public class BillingConstants
{
    public const int ApiVersion = 3;

    // Billing response codes
    public const int ResultOk = 0;
    public const int ResultUserCancelled = 1;
    public const int ResultBillingUnavailable = 3;
    public const int ResultItemUnavailable = 4;
    public const int ResultDeveloperError = 5;
    public const int ResultError = 6;
    public const int ResultItemAlreadyOwned = 7;
    public const int ResultItemNotOwned = 8;

    // Keys for the responses from InAppBillingService
    public const string ResponseCode = "RESPONSE_CODE";
    public const string SkuDetailsList = "DETAILS_LIST";
    public const string SkuDetailsItemList = "ITEM_ID_LIST";
    public const string SkuDetailsItemTypeList = "ITEM_TYPE_LIST";
    public const string BuyIntent = "BUY_INTENT";
    public const string InAppPurchaseData = "INAPP_PURCHASE_DATA";
    public const string InAppDataSignature = "INAPP_DATA_SIGNATURE";
    public const string InAppItemList = "INAPP_PURCHASE_ITEM_LIST";
    public const string InAppDataList = "INAPP_PURCHASE_DATA_LIST";
    public const string InAppSignatureList = "INAPP_DATA_SIGNATURE_LIST";
    public const string InAppContinuationToken = "INAPP_CONTINUATION_TOKEN";

    // Item types
    public const string ItemTypeInApp = "inapp";
    public const string ItemTypeSubscription = "subs";

    public const string BillingIntent = "com.android.vending.billing.InAppBillingService.BIND";
    public const string BillingPackageName = "com.android.vending";
    public const int PurchaseRequestCode = 1337;
}