diff --git a/ios/Classes/PluginScriptsJS/JavaScriptBridgeJS.swift b/ios/Classes/PluginScriptsJS/JavaScriptBridgeJS.swift
index 8f9aa385..3c65decc 100644
--- a/ios/Classes/PluginScriptsJS/JavaScriptBridgeJS.swift
+++ b/ios/Classes/PluginScriptsJS/JavaScriptBridgeJS.swift
@@ -176,7 +176,7 @@ let UTIL_JS_SOURCE = """
     },
     arrayBufferToString: function(arrayBuffer) {
         const uint8Array = new Uint8Array(arrayBuffer);
-        const data = uint8Array.reduce((acc, i) => acc += String.fromCharCode.apply(null, [i]), '');
+        const data = uint8Array.reduce(function(acc, i) { return acc += String.fromCharCode.apply(null, [i]); }, '');
         return data;
     },
     isBodyFormData: function(bodyString) {