You maybe know this but :hover doesn’t exist on touch screen devices. So when you design a responsive website, you should carefully plan when and where to use :hover interactions.
While it is implemented on mobile devices it is extremely buggy, mostly on iOS devices. On the other end you cant use :focus because it can be used only on a elements that support focus so a tags and buttons are ruled out. Also :active is no go on mobile devices.
In this case we can use jQuery to remedy this problem. 
Working example: http://jsfiddle.net/Gajotres/84Nug/
In this example I have used vmousedown,  vmouseup and vmousecancel events so I can test it on desktop / mobile devices alike. Just replace them with touchstart,  touchend and touchcancel.
touchcancel / vmousecancel is needed because sometimes button can stay in pressed state.
Code:
$(document).on('pagebeforeshow', '#index', function(){ 
    $(document).on('touchstart','.custom_header' ,function(){
        $(".custom_header").css("background","url('http://www.cesarsway.com/sites/default/files/cesarsway-images/features/2012/March/Puppies-and-Exercise.jpg') no-repeat center");
    }).on('touchend', function(){
        $(".custom_header").css("background","red");
    }).on("touchcancel", function() {
        $(".custom_header").css("background","red");
     }); 
});