diff --git a/docs/Reference.md b/docs/Reference.md
index 7d3752f..9257aca 100644
--- a/docs/Reference.md
+++ b/docs/Reference.md
@@ -102,7 +102,7 @@ Controls whether to adjust the content inset for web views that are placed behin
 
 ### `injectedJavaScript`
 
-Set this to provide JavaScript that will be injected into the web page when the view loads.
+Set this to provide JavaScript that will be injected into the web page when the view loads. Make sure the string evaluates to a valid type (`true` works) and doesn't otherwise throw an exception.
 
 | Type   | Required |
 | ------ | -------- |
diff --git a/ios/RNCWKWebView.m b/ios/RNCWKWebView.m
index 95ce13c..f386051 100644
--- a/ios/RNCWKWebView.m
+++ b/ios/RNCWKWebView.m
@@ -512,8 +512,12 @@ static NSString *const MessageHanderName = @"ReactNative";
           thenCall: (void (^)(NSString*)) callback
 {
   [self.webView evaluateJavaScript: js completionHandler: ^(id result, NSError *error) {
-    if (error == nil && callback != nil) {
-      callback([NSString stringWithFormat:@"%@", result]);
+    if (error == nil) {
+      if (callback != nil) {
+        callback([NSString stringWithFormat:@"%@", result]);
+      }
+    } else {
+      RCTLogError(@"Error evaluating injectedJavaScript: This is possibly due to an unsupported return type. Try adding true to the end of your injectedJavaScript string.");
     }
   }];
 }