This one is a very designer-heavy exercise. You're trying to understand the informational underpinning of the app.

These most often include:

• Sitemap: A tree-like visualization of different pages on a site (or within an app)
• System attributes: A list of all the entities withing the app, their characteristics and the way those entities are connected
• Flowchart: Visualization of all (or at least most) of the screens in the app and their mutual connections

Pro tips

To be effective at creating your information architecture, be sure to follow these recommendations:

• Be sure to structure the information in a logical and meaningful way, often through hierarchies, categories, or other systems that make content easy to understand and navigate.
• Be sure to clearly assign labels and names that are consistent to ensure that users can easily comprehend and identify content.
• Be sure to create intuitive navigation so Navigation: Creating intuitive pathways for users to move through information, enabling them to find what they need efficiently. This involves designing menus, links, and other navigation systems.
• Content Strategy: Develop a plan for creating, managing, and organizing content to ensure it meets user needs and business goals.

You can read more on the information architecture in the Design Handbook.