Update README.md

Author: coorasse

README.md

@@ -154,7 +154,7 @@ Again, check the example mailer included in the gem to see how to use it.
 
 ## Debug issues 
 
-* On Mac, open the `Console.app` to view the errors.
+* On Mac, you can open the *.pkpass files with "Pass Viewer". Open the `Console.app` to log possible error messages and filter by "Pass Viewer" process.
 * Check the logs on http://localhost:3000/passkit/dashboard/logs
 * In case of error "The passTypeIdentifier or teamIdentifier provided may not match your certificate, 
 or the certificate trust chain could not be verified." the certificate (p12) might be expired.