The document describes how to use the open API of CA Performance Management to customize data visualization through a hackathon session. It provides step-by-step instructions to deploy apps, configure custom attributes and groups, and leverage open API apps to create geo-location and connection data for a weather map visualization. Participants will learn how to deploy the necessary apps, configure device and interface attributes, validate the settings, and run the weather map app to visualize devices on an interactive map based on their geo-locations and connections. Customizations like map focus and color themes are also possible through app parameters.