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 open the Issuer redirect URL redirect the user to the IssuerAuthenticationURL by openeing it in an in-app browser. This is not allowed as it will not only break your iDEAL payment flow, but also creates secuity issues. You should offer the IssuerAuthenticationURL to the opertaing system of the mobile device of your user or make use of Chrome Custom Tabs (Android) or SafariViewController (iOS). For more detailed information, please refer to below passage from the iDEAL implementaton guidelines 10.3
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