On iPhone or iPad, I always have to log in again, even though I checked "Remember me". What should I do?

You may be using the Safari browser in "Private Browsing" mode or have opened portatour® in a private tab:

1. Turn off "Private Browsing" mode (see iPhone Help Browse the web privately in Safari on iPhone), or
2. open portatour® in a normal tab.

Then log in to portatour® again. Make sure to check Remember me on the login page (see User login in portatour®).