When an app includes location-based searching or matches, they sometimes lock you down to the location where you are using the app. Travel Mode, Passport, or Travel To… are examples of location-changing features where you can change the location of your search.
In some apps you don’t need to have a special feature to ‘travel’ – you can just change your location. In the apps where you do need a special travel mode, this feature is often limited to users with a premium subscription.