Hey @Pbalazs89,
The mechanism to open the link in a new window is not native or it is Javascript based and in newer versions of Safari, it asks the user (me) to allow the link to be opened. It does not do this in older versions and just simply blocks it that is why you perceive it as not working.
The button is not a native HTML element and Slider Revolution uses Javascript to open the link to a new window and though this is possible in Slider Revolution, this is not the natural way to open a link in a new window and some browsers might not allow this.

Please use a real link instead. The Button layer outputs a real link. Please use that.


I tested that in iPhone 5 Safari and that works.
Hope that helps.