Prevents zoom when interacting with `select`/text inputs on iOS, from jQM. Tested in iOS 6 and below.

ios-selectzoom.js

(function( $ ) {
    var meta = $( "meta[name=viewport]" ),
        initialContent = meta.attr( "content" ),
        disabledZoom = initialContent + ",maximum-scale=1, user-scalable=no",
        enabledZoom = initialContent + ",maximum-scale=10, user-scalable=yes",
        disabledInitially = /(user-scalable[\s]*=[\s]*no)|(maximum-scale[\s]*=[\s]*1)[$,\s]/.test( initialContent );

    $.zoom = {
        enabled: !disabledInitially,
        locked: false,
        disable: function( lock ) {
            if ( !disabledInitially && !$.zoom.locked ) {
                meta.attr( "content", disabledZoom );
                $.zoom.enabled = false;
                $.zoom.locked = lock || false;
            }
        },
        enable: function( unlock ) {
            if ( !disabledInitially && ( !$.zoom.locked || unlock === true ) ) {
                meta.attr( "content", enabledZoom );
                $.zoom.enabled = true;
                $.zoom.locked = false;
            }
        },
        restore: function() {
            if ( !disabledInitially ) {
                meta.attr( "content", initialContent );
                $.zoom.enabled = true;
            }
        }
    };

    // In many situations, iOS will zoom into the select upon tap, this prevents that from happening
    $("select, input").bind( "touchstart", function() {
        $.zoom.disable( true );
    }).bind( "mouseup", function() {
        setTimeout(function() {
            $.zoom.enable( true );
        }, 0);
    });

}( jQuery ));