c4-mobile
C4 Mobile — Architecture Diagrams for Mobile Applications
C4 model methodology with ready-to-use Mermaid templates for documenting Flutter apps and their backend services at multiple levels of abstraction.
C4 Levels — Which One to Use and When
Level 1, the Context diagram, answers the question "What does this application do and who uses it?" It is appropriate for all stakeholders, including non-technical ones. Level 2, the Container diagram, answers "What applications and services does it consist of?" It is aimed at the technical team and new members. Level 3, the Component diagram, answers "What is inside a particular container?" It is written for developers and should only be produced for genuinely complex modules. Level 4, the Deployment diagram, answers "Where does it run?" It is intended for DevOps and infrastructure decisions.
As a practical rule, Context and Container diagrams are sufficient for most projects. Component diagrams should only be drawn for internal structures that are actually complex.