Dynamic layout applications can only be used by VSys Live and VSys Web Advanced, not VSys Web.
Dynamic layout applications
Dynamic applications aren't visual like fixed ones - you don't see on your screen how the application is going to look when it's done - but they're much more flexible and easier to make consistent. Instead of putting the fields in the right places:
VSys Live renders them in the user's browser in a way that makes sense. Small browser window, large fonts, or both? You'll get a long application, but one that fits horizontally. Wide window and small fonts? VSys Live will put in line breaks only where it needs to, plus where you tell it to.
There is very rarely a good reason to use a fixed layout application with VSys Live. They're only supported for purposes of backwards-compatibility where those applications were created in the past. Best practice is to convert these older applications to dynamic layout applications: they'll work far better on mobile devices, scale better for users with vision issues, and will almost always look better as well!
Fixed layout applications
These applications have - as indicated by their name - a fixed layout. That is, you put the fields on the application exactly where you want them, and VSys Live renders them just as you've set.
Fixed layout applications are easy:
Fixed layout applications are hard and ugly:
Existing fixed layout applications can be left as-is: there's no immediate need to change them unless you want to. When you want to, right-click on the application and select Convert to a dynamic layout application to have VSys re-make the application in a dynamic layout, and all existing submitted and new applications will use the new layout. (After conversion, if the application is all wrong, just don't Save it and you'll have your old layout back.)
Or right-click and select Make a copy as a dynamic layout application. VSys will take your existing application, make a copy, and turn it into a dynamic layout application. Your old application remains unchanged.