Page zoom using mobile browsers can be a great way to view certain areas on a webpage, especially if it’s difficult to see a certain area of the page. However, with mobile versions of certain websites, it may not be a useful feature if your website is already optimized for mobile viewing.By disabling the zoom feature with the pinch-zoom/double-tap feature of mobile browsers, you can maintain the same viewable area of the website.
It is actually a very easy meta tag that you just need to include in the head tags of your page.
<meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1, user-scalable=0" />
That’s it. Really simple. However, as a word of caution, you shouldn’t add this if the page is not a mobile version.