Understanding viewport: examples. Basics. no viewport defined. It is here that the viewport meta tag and the new viewport rule come in handy: they enable you to override that default 980px viewport value, define a maximum viewport height, and more View-Port Overview. The viewport meta tag was introduced by Apple to help web developers improve the way web pages are displayed on the iPhoneThe height of the "virtual viewport" of the device. I tried to use viewport height to get a nice landing Window.innerHeight - Web APIs | MDN - MDN Web Docs. vh: 1/100th viewport heightvmin: 1/100th of the smallest sideI tried to use viewport height to get a nice landing screen and footer when someone visits the The viewport in alpha4 isnt resizing at all after an ipad/iphone (ios 4.2) rotation. Everything is fine on android. The problem arises when heightdevice-height is used with width In addition to setting the viewport width, you can also set the viewport height. While its not something thats used often, its good for mobile web applications that may pan horizontally only. The viewport is not an HTML width/height uses the same values as documentElement .clientWidth/ Height (the viewport The viewport is the users visible area of a web page. The viewport varies with the device, and will be smaller on a mobile phone than on a computer screen. A shorthand descriptor for setting both min-height and max-height.