Just as the concept of form navigation has changed now that users will be interacting with your forms on a variety of devices, where formerly you could have been certain that they would only be using a desktop computer or laptop. Indeed, we now group laptops with desk-bound computers and call them collectively "the desktop". The important distinction is that "the desktop" is now characterized by a large monitor and a pointing device (either a mouse or a trackpad).

 

Mobile devices have restricted screen space and the user interacts with them through a touch interface.

 

See Devices vs Desktop for more.

 

As a result, Legacy Layouts now are a thing of the past. What worked in hard copy will probably no longer work on a smartphone.

 

This early parts of this section of the Composer 4 Guide explores these issues a little. The section ends with Responsive Layout.

 

Also, forms these days will be consumed more in HTML rather than as PDF. User expect this. In fact waiting for a PDF form to load, which often take much longer than the HTML version of a form, is more unwanted friction for the user.