K2 Smart Forms allow users to create customizable forms without code using a drag-and-drop interface. The forms can integrate data from various systems using SmartObjects and be tied to workflows. The K2 Designer is used to create SmartObjects, views, pages, and workflows, while runtime forms provide the end user experience. Smart Forms support integration with many common business systems and allow reuse of components across applications and devices. However, Smart Forms also have some limitations related to copying/pasting in the designer, tight coupling between views and SmartObjects, and lack of action scripting capabilities.