Which of the following is NOT a custom attribute data type in the Braze SDK?

The attribute data types that are considered custom attributes in the Braze SDK include Boolean, Strings, and Dates. These data types enable you to track specific user attributes and behaviors that can be particularly beneficial for targeting and personalization in marketing campaigns.

Boolean attributes are used to represent true/false states, which can be useful for flagging user preferences or behaviors. Strings represent textual data, allowing for a wide range of customizable user attributes. Dates are also a recognized type that helps in tracking temporal events related to user engagement.

However, URLs, while they can be utilized within the SDK for features such as linking, are not categorized as a custom attribute data type in the way the other options are. They serve a different function and do not inherently represent a user attribute in the custom sense that Boolean, Strings, and Dates do. Therefore, identifying URLs as the option that is not a custom attribute data type reflects the understanding of how different data types are categorized within the Braze SDK.