If you offer iDEAL in your app and are experiencing problems or are receiving customer complaints with regard to redirects to (some) of the iDEAL Issuers, please make sure that you do not redirect the user to the redirect URL by opening it in an in-app browser. This is not allowed as it will not only break your iDEAL payment flow, but also creates security issues. You should offer the redirect URL to the operating system of the mobile device of your user or make use of Chrome Custom Tabs (Android) or SafariViewController (iOS).