gistfile1.js

// http://jasonwyatt.tumblr.com/post/10481498815/how-to-correctly-debounce-a-javascript-function
function debounce(fn, debounceDuration)
{
    debounceDuration = debounceDuration || 100;

    return function(){
        if(!fn.debouncing){
            var args = Array.prototype.slice.apply(arguments);
            fn.lastReturnVal = fn.apply(window, args);
            fn.debouncing = true;
        }
        clearTimeout(fn.debounceTimeout);
        fn.debounceTimeout = setTimeout(function(){
            fn.debouncing = false;
        }, debounceDuration);

        return fn.lastReturnVal;
    };
}

var win = $(window),
    win_width,
    win_height,
    resize_queue = [];

resize_queue.push(function()
{
    win_width = win.width();
    win_height = win.height();

    // do stuff ...
});

var doResize = function()
{
    for (var i = 0; i < resize_queue.length; i++) {
        if (typeof resize_queue[i] === 'function') {
            resize_queue[i]();
        }
    }
};

win.on('resize orientationchange', debounce(function(e) { doResize(); }, 50));

can be done without jQuery of course!

Or just CSS with height: 100vh; but be wary of the disastrous iOS bug...