diff --git a/shopify.php b/shopify.php
index 4c05b55..2694c76 100644
--- a/shopify.php
+++ b/shopify.php
@@ -1,5 +1,6 @@
 <?php
 
+	$shopify_app_version = "1.0.0";
 
 	function shopify_app_install_url($shop_domain, $api_key)
 	{
@@ -70,7 +71,7 @@ function curl_setopts_($ch, $method, $payload, $request_headers)
 				curl_setopt($ch, CURLOPT_MAXREDIRS, 3);
 				curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, true);
 				curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, 2);
-				curl_setopt($ch, CURLOPT_USERAGENT, 'HAC');
+				curl_setopt($ch, CURLOPT_USERAGENT, "ShopifyPHP-LegacyAuth-v{$shopify_app_version}");
 				curl_setopt($ch, CURLOPT_CONNECTTIMEOUT, 30);
 				curl_setopt($ch, CURLOPT_TIMEOUT, 30);
 
@@ -142,4 +143,4 @@ function __construct($info)
 		function getInfo() { $this->info; }
 	}
 
-?>
\ No newline at end of file
+?>