diff --git a/amazon/validator.go b/amazon/validator.go
index 0ac5f0e..5ef877a 100644
--- a/amazon/validator.go
+++ b/amazon/validator.go
@@ -101,13 +101,16 @@ func (c *Client) Verify(ctx context.Context, userID string, receiptID string) (I
 
 	resp, err := c.httpCli.Do(req)
 	if err != nil {
-		return result, fmt.Errorf("%v", err)
+		return result, err
 	}
 	defer resp.Body.Close()
 
 	if resp.StatusCode < 200 || resp.StatusCode >= 300 {
 		responseError := IAPResponseError{}
 		err = json.NewDecoder(resp.Body).Decode(&responseError)
+		if err != nil {
+			return result, err
+		}
 		return result, errors.New(responseError.Message)
 	}
 
diff --git a/amazon/validator_test.go b/amazon/validator_test.go
index 986eeef..373ffc5 100644
--- a/amazon/validator_test.go
+++ b/amazon/validator_test.go
@@ -6,6 +6,7 @@ import (
 	"fmt"
 	"net/http"
 	"net/http/httptest"
+	"net/url"
 	"os"
 	"reflect"
 	"testing"
@@ -175,11 +176,17 @@ func TestVerifyTimeout(t *testing.T) {
 	server, client := testTools(100, "timeout response")
 	defer server.Close()
 
-	expected := errors.New("")
 	ctx := context.Background()
 	_, actual := client.Verify(ctx, "timeout", "timeout")
-	if !reflect.DeepEqual(reflect.TypeOf(actual), reflect.TypeOf(expected)) {
-		t.Errorf("got %v\nwant %v", actual, expected)
+
+	// Actual should be a "request canceled" *url.Error
+	urlErr, ok := actual.(*url.Error)
+	if !ok {
+		t.Errorf("Expected *url.Error, got %T", actual)
+	}
+
+	if !urlErr.Timeout() {
+		t.Errorf("got %v\nwant timeout", actual)
 	}
 }
 
diff --git a/appstore/validator.go b/appstore/validator.go
index 1a0ff80..4786f01 100644
--- a/appstore/validator.go
+++ b/appstore/validator.go
@@ -98,7 +98,9 @@ func NewWithClient(client *http.Client) *Client {
 // Verify sends receipts and gets validation result
 func (c *Client) Verify(ctx context.Context, reqBody IAPRequest, result interface{}) error {
 	b := new(bytes.Buffer)
-	json.NewEncoder(b).Encode(reqBody)
+	if err := json.NewEncoder(b).Encode(reqBody); err != nil {
+		return err
+	}
 
 	req, err := http.NewRequest("POST", c.ProductionURL, b)
 	if err != nil {