App has ability to redirect customers to different website or pages based on zip codes customers submit. Often time merchants has multiple stores based on a region where this feature can come handy.
When you are creating a new zip code set, you would see option to enable "Zip code based redirection" for serviceable zip codes.
How it appears on store:
Note that setup lies within your zip code restrictions so please go to “Zip codes” > “Click on edit on a zip code set” > Scroll down and you would see "Zip code based redirection"