Not able to make calls from "Dynamics CRM for Phones"

I was under the impression that you would be able to make call directly from Dynamics CRM for phones.

But nothing happens when I click the "phone" icon like in the picture... Pressing the mail icon takes me to the e-mail app though, and I expected the phone-icon to take me to the "call-function" on the phone?

 

Am I missing something??