About Variables and Variable Sets
Variables allow you to dynamically define any element in your mobile application from within the Dynamic Yield admin. You paste a snippet of code in your mobile application and define the value in Dynamic Yield. For example, you might use a variable for a headline, image, or any other snippet of code you want to replace. This lets you make fast changes to your app without the need to redeploy it and submitting it for approval to the app store.
Variable Sets are groups of variables that also allow you to create variations and experiences to target different users with different values. For example, if you want to group a variable for a headline and one for an image, you could create a variable set that displays a particular headline/image combination for one audience, and a different combination for other audiences. You could also create a number of variations and utilize A/B testing to determine the best values to use for your variables.