How to ask user to change orientation to portrait if he/she rotates phone to landscape mode

[JimScott]

@sgibm

I've assembled some links that go over your subject - none of which I've utilized - I'm just the librarian ;->

@DBear's suggestion:

Block Rotation Smartphone

You can’t (and really shouldn’t ) block the rotation. But why not detect the orientation and display a message asking the user to use a certain orientation. if (window.innerHeight < window.innerWidth) { // portrait orientation // show a message that asks the user to use landscape mode myElement = document.getElementById('ELEMENT_ID') myElement.innerHTML = "Please use Landscape Orientation"; }

From stackoverflow, some ideas, including detecting device rotation: (as per a [post](http://forums.tumult.com/t/possible-to-disable-landscape-portrait-mode-per-layout/1645/4) by @Daniel in March 2015):

Blocking device rotation on mobile web pages