To solve the issue for HTML5 meta viewport, you can any of the following fix:
<meta name = "viewport" content = "user-scalable = no, initial-scale = 1, maximum-scale = 1, minimum-scale = 1, width = 400, height = device-height, target-densitydpi=medium-dpi" />
You can also try this:
<meta name = "viewport" content = "width=device-width, initial-scale = 1;"/>
Let us say you have a site width of 100px, then it won’t display the whole page, with
initial-scale = 1