Disable Pinch Zoom on Mobile Web

this will prevent any zoom action by the user in ios safari and also prevent the "zoom to tabs" feature:

document.addEventListener('gesturestart', function(e) {
    e.preventDefault();
    // special hack to prevent zoom-to-tabs gesture in safari
    document.body.style.zoom = 0.99;
});

document.addEventListener('gesturechange', function(e) {
    e.preventDefault();
    // special hack to prevent zoom-to-tabs gesture in safari
    document.body.style.zoom = 0.99;
});

document.addEventListener('gestureend', function(e) {
    e.preventDefault();
    // special hack to prevent zoom-to-tabs gesture in safari
    document.body.style.zoom = 0.99;
});

jsfiddle: https://jsfiddle.net/vo0aqj4y/11/

This is all I needed:

<meta name="viewport" content="user-scalable=no"/>

To everyone who said that this is a bad idea I want to say it is not always a bad one. Sometimes it is very boring to have to zoom out to see all the content. For example when you type on an input on iOS it zooms to get it in the center of the screen. You have to zoom out after that cause closing the keyboard does not do the work. Also I agree that when you put many I hours in making a great layout and user experience you don't want it to be messed up by a zoom.

But the other argument is valuable as well for people with vision issues. However In my opinion if you have issues with your eyes you are already using the zooming features of the system so there is no need to disturb the content.

EDIT: Because this keeps getting commented on, we all know that we shouldn't do this. The question was how do I do it, not should I do it.

Add this into your for mobile devices. Then do your widths in percentages and you'll be fine:

<meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no" />

Add this in for devices that can't use viewport too:

<meta name="HandheldFriendly" content="true" />