I knew that the certificate gives some problem, but it worked for qmc and not for hub?
It also worked for my Macbook Pro and Windows PC's, but not for my Iphone and Ipad.
But now the problem is solved when I allow http.
Thank you very much, now I can try to make some users to implement Qlik to my team.
as far as I learned and understood (please correct me if wrong) iOS from version 8.x on will not trust any self-signed certs anymore and thus does not allow access in general.
So the solution to use https with an iPad is to have a signed cert created by a trusted CA.
A free cert for everyone will hopefully be available at https://letsencrypt.org from September on.