Hi Jürgen.

I have found that this change is needed to force one onclick response when "Show Caption" is set to "always".

ResponsiveImage.js

   // on touch enabled devices use: first tab->show caption, 2nd tab->follow link
   $(".responsive_image_wrapper").on('click',function(e){
     if ("ontouchstart" in document.documentElement && $(this).find(".responsive_image_caption_wrapper.caption-show-hover").length > 0) {

.............

     }
   });

});

Yep, thanks. Will be in the next update.