This article shares some possible use cases your app could support, as well as a sample flow that could support each use case. This can be a helpful jumping off point as you plan your app's implementation.
If you have multiple event sites using your app, you may need to sync event categories across these sites. For example, if you've added a new city for some of your concerts, such as "Chicago," you’ll need to create a new category named "Chicago" and apply this change to other sites as well.
To sync the category across all sites:
Call Query Categories on the site where you created a new category.
Extract the entire category object. Remove unnecessary fields, like createdDate.
For all other sites, call Query Events and extract the IDs of all relevant events.
Call Create Category on the other sites, passing the new category to each.
Call Bulk Assign Events and assign the new category to all the previously extracted events.