Which item cannot be categorized as a column type in monday.com apps?

In monday.com, the various column types serve specific functions and allow users to organize and manage their data effectively. Text columns are used for entering and displaying text data, file columns allow users to upload and manage files directly within the board, and calendar columns are designed specifically to track dates, deadlines, and schedules visually.

On the other hand, monday.com apps themselves cannot be categorized as a column type. Apps are additional functionalities or integrations that enhance the capabilities of monday.com but do not function as a column within a board. Instead, they may provide features such as automation, reporting, or integration with other tools, but they do not represent data fields or types that can be implemented as columns in the way that text, file, or calendar columns do. This distinction is important as it highlights how columns in monday.com are specifically designed for data representation rather than being a standalone feature or application.