By using Event normalization, Ext JS 5 is able to run itself on touch screen devices. This normalization runs in an invisible way that translates mouse events into their equivalent functionality for the touch device. Consider the following example:

myDivElement.on('mousedown', function(e) {
    // event handling logic here
});

This is translated to the following:

myDivElement.on('touchstart', function(e) {
    // event handling logic here
});

Alternatively, it can be translated to this:

myDivElement.on('pointerdown', function(e) {
    // event handling logic here
});

These translations will be made depending on how the device supports each of them. It's important to mention that Ext JS cannot translate all touch interactions, so the events that are not translated must be covered on an individual basis.