Use conditional variables

Although you can’t directly change a variable’s value based on the Output Tags, there is a way to make your variables conditional: you can insert variables in a row where you need them and show only one of them with the specified Output Tag. 

Here's how you can implement this approach:

  1. Create a variable, each holding a unique value.
  2. Insert these variables in a row where you need them.
  3. In the source view, add conditions to these variables. It will look something like this:
    HTML
    <ch:var name="platform1" ch:include="Windows"/>

As a result, you will have only one of the values present when you specify an Output Tag: