diff --git a/appstore/validator.go b/appstore/validator.go
index b5dbe74..1faa23b 100644
--- a/appstore/validator.go
+++ b/appstore/validator.go
@@ -12,6 +12,7 @@ import (
 	"net/http"
 	"time"
 
+	"github.com/awa/go-iap/appstore/api"
 	"github.com/golang-jwt/jwt/v4"
 )
 
@@ -39,7 +40,7 @@ type Client struct {
 	httpCli       *http.Client
 }
 
-// list of errore
+// list of errors
 var (
 	ErrAppStoreServer = errors.New("AppStore server error")
 
@@ -214,3 +215,29 @@ func (c *Client) ParseNotificationV2WithClaim(tokenStr string, result jwt.Claims
 	})
 	return err
 }
+
+// IAPAPIClient is an interface to call validation API in App Store Server API
+type IAPAPIClient interface {
+	Verify(ctx context.Context, transactionId string) (interface{}, error)
+}
+
+type APIClient struct {
+	productionCli *api.StoreClient
+	sandboxCli    *api.StoreClient
+}
+
+func NewAPIClient(config api.StoreConfig) *APIClient {
+	prodConf := config
+	prodConf.Sandbox = false
+	sandboxConf := config
+	sandboxConf.Sandbox = true
+	return &APIClient{productionCli: api.NewStoreClient(&prodConf), sandboxCli: api.NewStoreClient(&sandboxConf)}
+}
+
+func (c *APIClient) Verify(ctx context.Context, transactionId string) (interface{}, error) {
+	result, err := c.productionCli.GetTransactionInfo(ctx, transactionId)
+	if err != nil && errors.Is(err, api.TransactionIdNotFoundError) {
+		result, err = c.sandboxCli.GetTransactionInfo(ctx, transactionId)
+	}
+	return result, err
+}