Which piece is crucial for enabling users to move through an app in a logical order?

The concept of sequence is vital for guiding users through an app in a logical order. It dictates the order in which users interact with various elements or screens, helping them understand how to progress through tasks and navigate the app effectively. A well-structured sequence ensures that users can easily follow along, completing one step before moving to the next, thus reducing confusion and enhancing the overall user experience.

For instance, when using a task-based app, the sequence allows users to complete a series of steps in a way that feels intuitive and coherent, making it easier for them to achieve their goals. By focusing on sequence, designers can create workflows that align with natural human behavior, minimizing cognitive load and facilitating smoother interactions.

While organization, hierarchy, and classification are important components of design, they primarily relate to how information is structured or categorized rather than the specific order in which actions should take place. This makes sequence the most critical factor for maintaining a logical flow in an app.